Vehicle suspension system for stable squat magnitude responses

ABSTRACT

A wheel suspension system having under powered acceleration a stable squat magnitude response.

This application is a divisional of U.S. application Ser. No.11/102,218, filed Apr. 7, 2005, currently pending, which is incorporatedherein by reference in its entirety.

BACKGROUND

This invention relates to suspension systems capable of maintaining astable squat response magnitude under powered vehicle acceleration.

Automobiles, bicycles, motorcycles, all terrain vehicles, and otherwheel driven vehicles are used for various purposes, includingtransportation and leisure. These vehicles are designed to use a powersource to drive, through a power transmission system, a wheel or wheels,which transfers rotary motion to the ground via tractive force between awheel or wheels and the ground. Vehicles are also used to traverse eventerrain like paved streets, and uneven terrain like off-road dirttrails. Off road trails are generally bumpier and allow for less wheeltraction than paved roads. A bumpier terrain is best navigated with avehicle that has a suspension system. A suspension system in a vehicleis aimed to provide a smoother ride for an operator or rider, andincrease wheel traction over varied terrain. Vehicle suspension systemsmay be employed on forward and on rearward wheels.

One undesirable effect of suspension systems is the loss of energy inthe way of suspension compression or extension during poweredacceleration. Such energy loss is particularly notable in vehicles thatare driven by low energy power sources, for example, bicycles and solarvehicles. For example, the average rider of a bicycle can exert only alimited amount of power or energy for a short period of time and an evenlesser amount for an extended period of time. Therefore, even a verysmall power loss can have a significant effect on rider performance andcomfort. Common vehicle tires require high suspension stiffness foroptimal traction and bump absorption, and common human physiologyrequires low suspension stiffness for bearable human comfort levels.Because of the differing requirements for operator comfort, tiretraction, and bump compliance, other undesirable effects of suspensionsystems can include loss of vehicle operator comfort due to a suspensionbeing too stiff for comfort, or loss of traction and bump absorption dueto a suspension being too soft for traction and bump absorption.Suspension travel is the distance a suspended wheel travels when thesuspension is moved from a fully extended state to a fully compressedstate. Suspension systems can exhibit wide variations in squat magnitudeas a suspension is compressed. Generally, due to suspension kinematics,the further a typical suspension is compressed, the wider the variationin squat magnitude becomes over the duration of the suspensioncompression from a fully extended to a fully compressed state. Thisvariation in squat magnitude means that the suspension cannot operate ata point of peak efficiency, or lowest amount of suspension movement,over its entire travel. This variation is squat can further compress orextend the suspension due to acceleration forces at different points inthe suspension travel. A suspension must be configured to attain idealbump apportion, comfort, or performance efficiency traits at a finitepoint in its suspension travel distance. All other points in thesuspension travel distance will exhibit some performance traits that maybe undesirable to the vehicle operator. In bicycles, suspension travelhas been increased for many designs and with these increases insuspension travel; the aforementioned energy loss has become even moreapparent to riders. But even for a vehicle with a high power energysource, any loss in energy reduces the vehicle's efficiency, for exampleits fuel efficiency. Where vehicles are used in a manner that requiresfrequent accelerations and deceleration (or positive and negativeaccelerations), the safety and comfort of the vehicle operator and theefficiency of the vehicle are particularly affected by excess chassismovement resulting from the vehicles geometry, including the geometryand design of its suspension systems.

A suspension system for a vehicle should be designed to minimize thevariance in suspension movement due to acceleration forces, and tominimize energy loss, comfort loss, and loss of ability to absorb bumps.Ultimately, the environmental impact of the vehicle is reduced. The needfor a suspension system that can better preserve a vehicles efficiencyand energy has therefore become more pressing. The present inventionprovides suspension system designs for vehicles that reduce these energylosses and additionally provided improved operator comfort or improvedtire traction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a is a side view of a chain driven vehicle using a driven wheelsuspension system that achieves a stable squat magnitude curve accordingto certain embodiments of the current invention. The vehicle is shownwith the driven wheel suspension system in an uncompressed state.

FIG. 1 b is a side view of a chain driven vehicle as shown in FIG. 1 awith the driven wheel suspension system in a completely compressedstate.

FIG. 1 c is an enlarged section of the side view of the chain drivenvehicle shown in FIGS. 1 a and 1 b with the driven wheel suspensionsystem in a completely uncompressed state.

FIG. 1 d is an enlarged section of the side view of the chain drivenvehicle shown in FIGS. 1 a, 1 b, and 1 c with the driven wheelsuspension system in a completely compressed state.

FIG. 2 a is a side view of a shaft driven vehicle using a driven wheelsuspension system that achieves a squat magnitude curve according tocertain embodiments of the current invention. The vehicle is shown withthe driven wheel suspension system in an uncompressed state.

FIG. 2 b is a side view of a shaft driven vehicle as shown in FIG. 2 awith the driven wheel suspension system in a completely compressedstate.

FIG. 2 c is an enlarged section of the side view of the shaft drivenvehicle shown in FIGS. 2 a and 2 b with the driven wheel suspensionsystem in a completely uncompressed state.

FIG. 2 d is an enlarged section of the side view of the shaft drivenvehicle shown in FIGS. 2 a, 2 b, and 2 c with the driven wheelsuspension system in a completely compressed state.

FIG. 3 a is a side view of a spindle driven vehicle using a driven wheelsuspension system that achieves a squat magnitude curve according tocertain embodiments of the current invention. The vehicle is shown withthe driven wheel suspension system in an uncompressed state.

FIG. 3 b is a side view of a spindle driven vehicle as shown in FIG. 3 awith the driven wheel suspension system in a completely compressedstate.

FIG. 3 c is an enlarged section of the side view of the spindle drivenvehicle shown in FIGS. 3 a and 3 b with the driven wheel suspensionsystem in a completely uncompressed state.

FIG. 3 d is an enlarged section of the side view of the spindle drivenvehicle shown in FIGS. 3 a, 3 b, and 3 c with the driven wheelsuspension system in a completely compressed state.

FIG. 4 a is a side view of a chain driven vehicle using a driven wheelsuspension system that achieves a stable squat magnitude curve accordingto certain embodiments of the current invention. The vehicle is shownwith the driven wheel suspension system in an uncompressed state.

FIG. 4 b is a side view of a chain driven vehicle as shown in FIG. 4 awith the driven wheel suspension system in a completely compressedstate.

FIG. 5 a is a side view of a shaft driven vehicle using a driven wheelsuspension system that achieves a squat magnitude curve according tocertain embodiments of the current invention. The vehicle is shown withthe driven wheel suspension system in an uncompressed state.

FIG. 5 b is a side view of a shaft driven vehicle as shown in FIG. 5 awith the driven wheel suspension system in a completely compressedstate.

FIG. 6 a is a side view of a spindle driven vehicle using a driven wheelsuspension system that achieves a squat magnitude curve according tocertain embodiments of the current invention. The vehicle is shown withthe driven wheel suspension system in an uncompressed state.

FIG. 6 b is a side view of a spindle driven vehicle as shown in FIG. 6 awith the driven wheel suspension system in a completely compressedstate.

FIG. 7 a shows a squat magnitude curve for suspension systems accordingto certain embodiments of the invention graphed on a squat magnitudecurve graph as disclosed herein. This curve is produced by suspensionkinematical geometry as shown in FIGS. 2 a, 2 b, 2 c, 2 d, 3 a, 3 b, 3c, 3 d, 5 a, 5 b, 6 a, and 6 b.

FIG. 7 b shows a squat magnitude curve for suspension systems accordingto certain embodiments of the invention graphed on a squat magnitudecurve graph as disclosed herein. This curve is produced by suspensionkinematical geometry as shown in FIGS. 2 a, 2 b, 2 c, 2 d, 3 a, 3 b, 3c, 3 d, 5 a, 5 b, 6 a, and 6 b.

FIG. 7 c shows the squat magnitude curve shown in FIG. 7 a forsuspension systems according to certain embodiments of the invention asgraphed on a squat magnitude curve graph as disclosed herein. The curveshown here results from the curve shown in FIG. 7 a by changing thescale of the vertical y-axis while maintaining the scale of thehorizontal x-axis. This curve is produced by suspension kinematicalgeometry as shown in FIGS. 2 a, 2 b, 2 c, 2 d, 3 a, 3 b, 3 c, 3 d, 5 a,5 b, 6 a, and 6 b and shows upper and lower bounds for determining apercent squat magnitude variation.

FIG. 8 shows the squat magnitude curve shown in FIG. 7 a for suspensionsystems according to certain embodiments of the invention as graphed ona squat magnitude curve graph as disclosed herein. The curve shown hereresults from the curve shown in FIG. 7 a by changing the scale of thevertical y-axis while maintaining the scale of the horizontal x-axis.This curve is produced by suspension kinematical geometry as shown inFIGS. 2 a, 2 b, 2 c, 2 d, 3 a, 3 b, 3 c, 3 d, 5 a, 5 b, 6 a, and 6 b andillustrates the varying slope of a squat magnitude curve of theinvention.

FIG. 9 shows a squat magnitude curve for suspension systems according tocertain embodiments of the invention graphed on a squat magnitude curvegraph as disclosed herein. This curve is produced by suspensionkinematical geometry as shown in FIGS. 1 a, 1 b, 1 c, and 1 d.

FIG. 10 shows the squat magnitude curve shown in FIG. 9 for suspensionsystems according to certain embodiments of the invention as graphed ona squat magnitude curve graph as disclosed herein. The curve shown hereresults from the curve shown in FIG. 9 by changing the scale of thevertical y-axis while maintaining the scale of the horizontal x-axis.This curve is produced by suspension kinematical geometry as shown inFIGS. 1 a, 1 b, 1 c, and 1 d and shows upper and lower bounds fordetermining a percent squat magnitude variation.

FIG. 11 shows a squat magnitude curve for suspension systems accordingto certain embodiments of the invention graphed on a squat magnitudecurve graph as disclosed herein. This curve is produced by suspensionkinematical geometry as shown in FIGS. 4 a, and 4 b.

FIG. 12 shows the squat magnitude curve shown in FIG. 11 for suspensionsystems according to certain embodiments of the invention as graphed ona squat magnitude curve graph as disclosed herein. The curve shown hereresults from the curve shown in FIG. 11 by changing the scale of thevertical y-axis while maintaining the scale of the horizontal x-axis.This curve is produced by suspension kinematical geometry as shown inFIGS. 4 a, and 4 b and shows upper and lower bounds for determining apercent squat magnitude variation.

FIG. 13 shows an instant force center that follows a defined instantforce center path with an instant force center path focus as projectedby compressible chain driven vehicle suspensions of the invention.

FIG. 14 is a side view of a vehicle with a center of mass shown withkinematical geometry used to determine a squat magnitude definitionpoint.

FIGS. 15-37 show alternative embodiments of suspension systemscomprising a squat magnitude curve of the invention. Each embodimentshown includes a spring/damper unit (small irregular box) and differentframe members (thicker lines) interconnected through pivots (smallcircles).

FIG. 38 is a side view of a chain driven vehicle using a driven wheelsuspension system first shown in FIG. 4 a that achieves a stable squatmagnitude curve according to certain embodiments of the currentinvention. The vehicle is shown with the driven wheel suspension systemin an uncompressed state. The vehicle uses a driven idler cog to definea chain force line.

FIG. 39 is a side view of a shaft or spindle driven vehicle using adriven wheel suspension system that achieves a stable squat magnitudecurve according to certain embodiments of the current invention. Thevehicle is shown with the driven wheel suspension system in anuncompressed state. The vehicle suspension system uses carriermanipulation tracks and carrier manipulation sliders to define wheelcarrier link movement.

FIG. 40 is a side view of a shaft or spindle driven vehicle using adriven wheel suspension system that achieves a stable squat magnitudecurve according to certain embodiments of the current invention. Thevehicle is shown with the driven wheel suspension system in ancompressed state. The vehicle suspension system uses carriermanipulation tracks and carrier manipulation sliders to define wheelcarrier link movement.

FIG. 41 is a side view of a shaft or spindle driven vehicle using adriven wheel suspension system that achieves a stable squat magnitudecurve according to certain embodiments of the current invention. Thevehicle is shown with the driven wheel suspension system overlaid inboth an uncompressed and compressed state. The vehicle suspension systemuses carrier manipulation tracks and carrier manipulation sliders todefine wheel carrier link movement.

FIG. 42 is a side view of a shaft or spindle driven vehicle using adriven wheel suspension system that achieves a stable squat magnitudecurve according to certain embodiments of the current invention. Thevehicle is shown with the driven wheel suspension system overlaid inboth an uncompressed and compressed state. The vehicle suspension systemuses carrier manipulation links to define wheel carrier link movement.

SUMMARY OF THE INVENTION

The current invention relates to new suspension systems for vehicles,for example, bicycles, motorcycles, cars, SUVs, trucks, two wheelvehicles, four wheel vehicles, front wheel suspension vehicles, drivenwheel suspension vehicles, and any other kind of vehicle with asuspension system. In certain embodiments of the invention, a suspensionsystem of the invention is capable of facilitating a stable squatmagnitude response. In certain preferred embodiments, a suspensionsystem of the invention lowers the energy loss during vehicleacceleration. This energy loss can be a result of unwanted suspensionextension or compression due to internal chassis forces which aregoverned by the vehicle suspension kinematics, powertrain layout,vehicle layout, and orientation. In certain preferred embodiments, asuspension system of the invention is capable of lowering energy lossand/or increase vehicle operator comfort resulting from squat byproducing a stable anti-squat magnitude response. An anti-squatmagnitude response of a suspension system of the invention, in certainembodiments, varies along suspension travel of the vehicle. In certainembodiments of the invention, a wheel suspension system comprises asquat magnitude curve with said squat magnitude curve having a stablerate of squat magnitude as the suspension system moves from a beginningpoint in the wheel travel to an ending point in the wheel travel.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a squat magnitude curve having a stable squat magnitudeand with said squat magnitude having a variation varying as thesuspension system moves from a beginning point in the wheel traveltowards an ending point in the wheel travel increase.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a squat magnitude curve with said squat magnitude curvehaving a stable squat magnitude and with said squat magnitude increasingand decreasing as the suspension system moves from a beginning point inthe wheel travel towards an ending point in the wheel travel increase.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a squat magnitude curve with said squat magnitude curvehaving a stable squat magnitude and with said squat magnitude decreasingand increasing as the suspension system moves from a beginning point inthe wheel travel towards an ending point in the wheel travel increase.

Certain embodiments of the invention comprise a wheel suspension designthat uses a tuned squat magnitude response to reduce poweredacceleration induced suspension movement at tactical points during thedriven wheel suspension travel. A vehicle designed to use a preferredembodiment of the invention can accelerate under power with a loweramount of energy loss and a more stable vehicle chassis than knownsystems throughout wheel suspension travel distance.

The present invention provides suspension system designs for vehiclesthat reduce energy loss during powered acceleration. The presentinvention provides suspension system designs for vehicles that reduceexcess suspension movement and improve operator comfort during poweredacceleration.

In certain embodiments of the invention, a wheel suspension systemcomprises a wheel connected to a wheel carrier link and said wheelcarrier link connected to spring damper means; and isolating said wheelfrom a frame structure with the wheel suspension system having a squatmagnitude curve with said squat magnitude curve having a stable rate ofsquat magnitude as the suspension system moves from a beginning point inthe wheel travel to an ending point in the wheel travel.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a wheel connected to a wheel carrier link and saidwheel carrier link connected to spring damper means; and isolating saidwheel from a frame structure with the wheel suspension system having asquat magnitude curve with said squat magnitude curve having a stablesquat magnitude and with said squat magnitude having a variation varyingas the suspension system moves from a beginning point in the wheeltravel towards an ending point in the wheel travel increase.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a wheel connected to a wheel carrier link and saidwheel carrier link connected to spring damper means; and isolating saidwheel from a frame structure with the wheel suspension system having asquat magnitude curve with said squat magnitude curve having a stablesquat magnitude and with said squat magnitude increasing and decreasingas the suspension system moves from a beginning point in the wheeltravel towards an ending point in the wheel travel increase.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a wheel connected to a wheel carrier link and saidwheel carrier link connected to spring damper means; and isolating saidwheel from a frame structure with the wheel suspension system having asquat magnitude curve with said squat magnitude curve having a stablesquat magnitude and with said squat magnitude decreasing and increasingas the suspension system moves from a beginning point in the wheeltravel towards an ending point in the wheel travel increase.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a shaft driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in the samedirection, and said first and second links connecting said wheel carrierlink to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in an upwards direction as thesuspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a shaft driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in oppositedirections, and said first and second links connecting said wheelcarrier link to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in an upwards direction as thesuspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a spindle driven wheel connected to a wheel carrierlink and said wheel carrier link connected to a first link and a secondlink; with said first and second links rotating together in the samedirection, and said first and second links connecting said wheel carrierlink to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in an upwards direction as thesuspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a spindle driven wheel connected to a wheel carrierlink and said wheel carrier link connected to a first link and a secondlink; with said first and second links rotating together in oppositedirections, and said first and second links connecting said wheelcarrier link to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in an upwards direction as thesuspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a shaft driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in the samedirection, and said first and second links connecting said wheel carrierlink to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in a direction horizontally closer tothe driven wheel rotation axis as the suspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a shaft driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in oppositedirections, and said first and second links connecting said wheelcarrier link to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in a direction horizontally closer tothe driven wheel rotation axis as the suspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a spindle driven wheel connected to a wheel carrierlink and said wheel carrier link connected to a first link and a secondlink; with said first and second links rotating together in the samedirection, and said first and second links connecting said wheel carrierlink to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in a direction horizontally closer tothe driven wheel rotation axis direction as the suspension iscompressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a spindle driven wheel connected to a wheel carrierlink and said wheel carrier link connected to a first link and a secondlink; with said first and second links rotating together in oppositedirections, and said first and second links connecting said wheelcarrier link to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in a direction horizontally closer tothe driven wheel rotation axis as the suspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a shaft driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in the samedirection, and said first and second links connecting said wheel carrierlink to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in a direction upwards in relation togravity and horizontally closer to the driven wheel rotation axis as thesuspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a shaft driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in oppositedirections, and said first and second links connecting said wheelcarrier link to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in a direction upwards in relation togravity and horizontally closer to the driven wheel rotation axis as thesuspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a spindle driven wheel connected to a wheel carrierlink and said wheel carrier link connected to a first link and a secondlink; with said first and second links rotating together in the samedirection, and said first and second links connecting said wheel carrierlink to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in a direction upwards in relation togravity and horizontally closer to the driven wheel rotation axisdirection as the suspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a spindle driven wheel connected to a wheel carrierlink and said wheel carrier link connected to a first link and a secondlink; with said first and second links rotating together in oppositedirections, and said first and second links connecting said wheelcarrier link to a frame structure, isolating said wheel from the framestructure. Said first link and said second link having projected linkforce lines and said first link projected force line intersecting saidsecond link projected force line to form an instant force center, withsaid instant force center moving in a direction upwards in relation togravity and horizontally closer to the driven wheel rotation axis as thesuspension is compressed.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a chain driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in the samedirection, and said first and second links connecting said wheel carrierlink to a frame structure, isolating said wheel from the framestructure. Said chain driven wheel is connected to a driven cog, whichis driven by a driven chain, which is driven by a driving cog. Alldriving and driven cogs have measurable pitch diameters. Said first linkand said second link having projected link force lines and said firstlink projected force line intersecting said second link projected forceline to form an instant force center, with said instant force centertranscribing an instant force center path, and with said instant forcecenter path having a variable or constant instant force center pathfocus, and with said instant force center path focus lying within thearea inside the pitch diameter of the driving cog for part or all of thesuspension travel.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a chain driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in oppositedirections, and said first and second links connecting said wheelcarrier link to a frame structure, isolating said wheel from the framestructure. Said chain driven wheel is connected to a driven cog, whichis driven by a driven chain, which is driven by a driving cog. Alldriving and driven cogs have measurable pitch diameters. Said first linkand said second link having projected link force lines and said firstlink projected force line intersecting said second link projected forceline to form an instant force center, with said instant force centertranscribing an instant force center path, and with said instant forcecenter path having a variable or constant instant force center pathfocus, and with said instant force center path focus lying within thearea inside the pitch diameter of the driving cog for part or all of thesuspension travel.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a chain driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in the samedirection, and said first and second links connecting said wheel carrierlink to a frame structure, isolating said wheel from the framestructure. Said chain driven wheel is connected to a driven cog, whichis driven by a driven chain, which is driven by a driving cog. Saiddriven chain has a chain force line, which is altered by a driven idlercog with a measurable pitch diameter. Said first link and said secondlink having projected link force lines and said first link projectedforce line intersecting said second link projected force line to form aninstant force center, with said instant force center transcribing aninstant force center path, and with said instant force center pathhaving a variable or constant instant force center path focus, and withsaid instant force center path focus lying within the area inside thepitch diameter of the driven idler cog for part or all of the suspensiontravel.

In certain embodiments of the invention, a compressible wheel suspensionsystem comprises a chain driven wheel connected to a wheel carrier linkand said wheel carrier link connected to a first link and a second link;with said first and second links rotating together in oppositedirections, and said first and second links connecting said wheelcarrier link to a frame structure, isolating said wheel from the framestructure. Said chain driven wheel is connected to a driven cog, whichis driven by a driven chain, which is driven by a driving cog. Saiddriven chain has a chain force line, which is altered by a driven idlercog with a measurable pitch diameter. Said first link and said secondlink having projected link force lines and said first link projectedforce line intersecting said second link projected force line to form aninstant force center, with said instant force center transcribing aninstant force center path, and with said instant force center pathhaving a variable or constant instant force center path focus, and withsaid instant force center path focus lying within the area inside thepitch diameter of the driven idler cog for part or all of the suspensiontravel.

DETAILED DESCRIPTION

Vehicles must be accelerated against their environment to propel anoperator or rider across terrain. In order to accelerate these vehicles,a certain amount of energy must be exerted and transformed into rotarymotion at a wheel or plurality of wheels. Suspended wheeled vehicleenergy conversion types are widely varied. Some vehicles like bicycles,tricycles, and pedal cars use converted human energy as the drive unit.Other vehicles use electric motors or combustion engines, as their driveunit. These electric motors and combustion engines extract rotary motionthrough the controlled release of chemically stored energy.

Almost all vehicle types use some sort of rotary motion transmissionsystem to transfer rotational force from a drive unit to a wheel orplurality of wheels. A simple bicycle or motorcycle or all terrainvehicle uses a chain or belt to transfer power from a drive unit to awheel. These chain or belt drive transmissions typically use onesprocket in the front which is coupled to a drive system and onesprocket in the rear which is coupled to a wheel.

More complex bicycles, motorcycles, all terrain vehicles, andautomobiles use a shaft drive system to transfer power from a drivesystem to a driven wheel or wheels. These shaft drive systems transferpower through a rotating shaft that is usually reasonably perpendicularto the driven wheel spinning axis, with power transferred to the drivenwheel via a bevel, spiral bevel, hypoid, worm gear drivetrain, or someother means. These single sprocket chain and belt, and shaft drivenvehicles can use a direct driven single speed arrangement, where driveunit output shaft speed and torque is transferred to the driven wheel ata constant unchanging ratio. These single sprocket chain and belt, andshaft driven vehicles can also use a commonly found multi speedarrangement, where drive unit output shaft speed and torque istransferred to the driven wheel at a variable ratio through operatorselected or automatically selected ratio changing mechanisms.

A bicycle with a more advanced design includes gear changing systemsthat have clusters of selectable front chainrings and rear sprockets.These gear changing systems give the bicycle rider a selectablemechanical advantage for use during powered acceleration. The mechanicaladvantage selection, allows a rider spinning a front sprocket clustervia crank arms, to attain lower revolution speed and higher torquevalues, or conversely, higher revolution speed and lower torque valuesat a driven wheel.

The current invention, in certain embodiments, is directed at suspensionsystems that can maintain low energy loss under powered acceleration ofthe vehicle, for example, a bicycle, a motorcycle, a car, an SUV, atruck, or any other kind of vehicle. Suspension systems of the currentinvention are useful for a large variety of vehicles, including, but notlimited to, human powered vehicles, off road use vehicles with longdisplacement suspension, high efficiency road going vehicles, and othervehicles.

A vehicle suspension system isolates a vehicle chassis from forcesimparted on the vehicle when traversing terrain by allowing thevehicle's ground contact points to move away from impacts at the terrainlevel and in relation to the vehicle chassis by a compressiblesuspension movement. The compressible suspension movement that isolatesa chassis from these impacts is called suspension displacement orsuspension travel. Compressible suspension travel has a beginning pointwhere the suspension is in a completely uncompressed state, and anending point of displacement, where the suspension is in a completelycompressed state. Suspension travel displacement is measured in adirection parallel to and against gravity when the vehicle is on levelground with the suspension fully extended. This measurement direction isalways measured first with the vehicle on level ground with thesuspension fully extended, and remains constant to the vehicle chassiswhen measuring suspension travel under circumstances where the vehicleis not placed on level ground or when suspension is compressed. Incertain preferred embodiments, a suspension system of the invention usesa tuned squat magnitude curve to provide an amount of squat closer to orhigher in the range of the squat condition known as anti squat throughthe duration of a suspension travel displacement. As a suspension systemof the invention is compressed, a damper unit is compressed. Throughoutthis entire disclosure, a damper unit may be discussed using the exampleof a spring or spring damper, however, it is understood that any type ofdamper unit may be employed under the various embodiments of thisinvention and that a spring or spring damper is merely a variation of adamper unit. A suspended wheel has a compressible wheel suspensiontravel distance that features a beginning travel point where thesuspension is completely uncompressed to a point where no furthersuspension extension can take place, and an end travel point where asuspension is completely compressed to a point where no furthersuspension compression can take place. Due to the connection between thespring damper unit, and the rear wheel through suspension components, asthe suspended wheel moves through its axle path, spring force at thewheel rises. At the beginning of the wheel suspension travel distance,when the suspension is in a completely uncompressed state, the spring isin a state of least compression, and the suspension is easilycompressed. As this spring or damper unit is compressed, the forceoutput from the spring damper unit rises.

The Figures in this disclosure use the following numbers and terms;driven wheel (1); wheel carrier link (2); first carrier manipulationlink (3); second carrier; manipulation link (4); chain force vector (5);driving force vector (6); squat force vector (7); first carriermanipulation link force vector (8); second carrier manipulation linkforce vector (9); squat definition point (10); squat layout line (11);lower squat measurement definition line (12); measured squat distance(13); driven wheel axle path (14); driven wheel suspension traveldistance (15); vehicle chassis (16); stable squat magnitude curve (17);squat magnitude curve upper bound (18); squat magnitude curve lowerbound (19); first link fixed pivot (20); second link fixed pivot (21);first link floating pivot (22); second link floating pivot (23); instantforce center (24); driven wheel rotation axis (25); chain force vectorand driving force vector intersection point (26); driving cog (27);driven cog (28); driving cog rotation axis (29); center of the forwardwheel tire to ground contact patch (30); center of the driven wheel tireto ground contact patch (31); vehicle center of sprung mass (32); 200percent squat point (33); 200 percent measurement value (34); forwardwheel (35); direction of gravity (36); squat magnitude definition point(37); squat magnitude (38); center of mass intersection vector (39);squat magnitude definition vector (40); percent squat magnitudevariation (41); first squat magnitude curve slope (42); first squatmagnitude curve slope (42); second squat magnitude curve slope (43);third squat magnitude curve slope (44); instant force center path (45);instant force center path focus (46); pitch diameter (47); driven idlercog (48); driven idler cog rotation axis (49); spring damper unit (50);first carrier manipulation track (51); second carrier manipulation track(52); first carrier manipulation slider (53); second carriermanipulation slider (54); first carrier manipulation slider force vector(55); second carrier manipulation slider force vector (56); firstcarrier manipulation slider force vector uncompressed (57); secondcarrier manipulation slider force vector uncompressed (58); firstcarrier manipulation slider force vector compressed (59); second carriermanipulation slider force vector compressed (60); first carriermanipulation link force vector uncompressed (61); second carriermanipulation link force vector uncompressed (62); first carriermanipulation link force vector compressed (63); second carriermanipulation link force vector compressed (64); instant force centerposition uncompressed (65); instant force center position compressed(66); instant force center upward movement (67); instant force centerrearward movement (68); first carrier manipulation slider pivot (69);second carrier manipulation slider pivot (70)

FIG. 1 a shows certain embodiments of the invention relating to chaindriven vehicles and it presents a graphical method useful to attain asquat point measurement, and a graphical method to attain suspensiongeometry kinematical layout from an existing desired measured squatpoint. Shown in FIG. 1 a are the following: driven wheel (1); wheelcarrier link (2); first carrier manipulation link (3); second carriermanipulation link (4); chain force vector (5); driving force vector (6);squat force vector (7); first carrier manipulation link force vector(8); second carrier manipulation link force vector (9); squat definitionpoint (10); squat layout line (11); lower squat measurement definitionline (12); measured squat distance (13); driven wheel axle path (14);driven wheel suspension travel distance (15); vehicle chassis (16);center of the forward wheel tire to ground contact patch (30); center ofthe driven wheel tire to ground contact patch (31); direction of gravity(36).

FIG. 1 a exemplifies that as the driven wheel 1 suspension system iscompletely uncompressed in its driven wheel suspension travel distance15; its squat force vector 7 is shown in relation to the vehicle chassis16. The squat force vector's 7 measured squat distance 13 which ismeasured as the perpendicular distance between the lower squatmeasurement definition line 12 and the squat definition point 10, isalso shown in FIG. 1 a. The squat measurement definition line 12 beginsat the center of the driven wheel tire to ground contact patch 30, andis plotted parallel to and against the direction of gravity 36,terminating at a further point. As the suspension system is compressedthrough its driven wheel suspension travel distance 15, change inmeasured squat distance 13 over the driven wheel suspension traveldistance15 is used to create a squat magnitude curve 17.

FIG. 1 b shows a side view of a chain driven vehicle as shown in FIG. 1a with the driven wheel suspension system in a completely compressedstate. Certain embodiments are further exemplified, for example, vectorsuseful to a graphical method to attain a squat point measurement areshown. Also exemplified is a graphical method useful to attainsuspension geometry kinematical layout from an existing desired measuredsquat point. Shown in FIG. 1 b in addition to what is presented in FIG.1 a, are the following: first link fixed pivot (20); second link fixedpivot (21); first link floating pivot (22); second link floating pivot(23); instant force center (24); driven wheel rotation axis (25); chainforce vector and driving force vector intersection point (26); drivingcog (27); driven cog (28); driving cog rotation axis (29).

FIG. 1 b exemplifies that as the driven wheel 1 suspension system iscompletely compressed through its driven wheel suspension traveldistance 15, its squat force vector 7 moves in relation to the vehiclechassis 16. The squat force vector's 7 measured squat distance 13, whichis measured as the perpendicular distance between the lower squatmeasurement definition line 12 and the squat definition point 10,decreases in relation to the measured squat distance 13 shown in FIG. 1a. This change in measured squat distance 13 over the driven wheelsuspension travel distance 15, in certain preferred embodiments, is usedto create a squat magnitude curve 17. FIG. 1 b shows the graphicalmethod used to obtain a squat magnitude curve 17 from chain drivenvehicle geometry, or chain driven vehicle geometry from a squatmagnitude curve 17. In the vehicle shown in FIG. 1 b, a driven wheel 1is attached to a wheel carrier link2, which pivots at one end of anfirst carrier manipulation link 3. The first carrier manipulation link 3is pivotally attached to the vehicle chassis 16 at the first link fixedpivot 20. A second carrier manipulation link 4 is also attached to thewheel carrier link2. This second carrier manipulation link 4 is attachedto the vehicle chassis 16 at a second link fixed pivot 21. An firstcarrier manipulation link force vector 8 is graphed coincident to thewheel carrier link2 upper pivot and the first link fixed pivot 20. Thefirst carrier manipulation link force vector 8 is graphed so that itintersects a second carrier manipulation link force vector 9, which isgraphed coincident to the wheel carrier link2 lower pivot and the secondlink fixed pivot 21. The intersection point of the first carriermanipulation link force vector 8 and the second carrier manipulationlink force vector 9 is called the instant force center 24. A drivingforce vector 6 is graphed beginning at the driven wheel rotation axis25, and passes through the instant force center 24. A chain force vector5 is drawn tangent to the tops of the driving cog 27 and driven cog 28,and intersects the driving force vector 6 at a chain force vector anddriving force vector intersection point 26. The squat force vector 7 isgraphed from a beginning point at the center of the driven wheel tire toground contact patch 31, and passes through the chain force vector anddriving force vector intersection point 26, before it terminates on asquat layout line 11. The intersection of the squat force vector 7 andthe squat layout line is called the squat layout point 10. The squatlayout line 11 is graphed at a perpendicular angle to gravitationalforce. A lower squat measurement definition line 12 is graphed beginningat the center of the driven wheel tire to ground contact patch 31 andterminating perpendicular and coincident to the squat layout line 11.The perpendicular measurement from the lower squat measurementdefinition line 12 to the squat layout point 10 is called the measuredsquat distance 13. This measured squat distance 13 changes as drivenwheel suspension travel distance 15 compresses, and is used to create asquat magnitude curve 17 in a squat magnitude curve graph as shown inFIG. 9 and FIG. 10.

FIG. 1 c shows an enlarged section of the side view of the chain drivenvehicle shown in FIGS. 1 a and 1 b with the driven wheel suspensionsystem in a completely uncompressed state.

FIG. 1 d shows an enlarged section of the side view of the chain drivenvehicle shown in FIGS. 1 a, 1 b, and 1 c with the driven wheelsuspension system in a completely compressed state. FIGS. 1 c and 1 dfurther exemplify certain embodiments, for example, points and vectorsuseful for a graphical method used to attain a squat point measurement,and a graphical method to attain suspension geometry kinematical layoutfrom an existing desired measured squat point.

FIG. 2 a shows certain embodiments of the invention relating to shaftdriven vehicles and it presents a graphical method useful to attain asquat point measurement, and a graphical method to attain suspensiongeometry kinematical layout from an existing desired measured squatpoint. Shown in FIG. 2 a are the following: driven wheel (1); wheelcarrier link (2); first carrier manipulation link (3); second carriermanipulation link (4); squat force vector (7); first carriermanipulation link force vector (8); second carrier manipulation linkforce vector (9); squat definition point (10); squat layout line (11);lower squat measurement definition line (12); measured squat distance(13); driven wheel axle path (14); driven wheel suspension traveldistance (15); vehicle chassis (16); center of the forward wheel tire toground contact patch (30); center of the driven wheel tire to groundcontact patch (31); direction of gravity (36).

FIG. 2 a exemplifies that as the driven wheel 1 suspension system iscompletely uncompressed in its driven wheel suspension travel distance15, its defined squat force vector 7 is shown in relation to the vehiclechassis 16. The squat force vector's 7 measured squat distance 13, whichis measured as the perpendicular distance between the lower squatmeasurement definition line 12 and the squat definition point 10, isshown in FIG. 2 a. The squat measurement definition line 12 begins atthe center of the driven wheel tire to ground contact patch 30, and isplotted parallel to and against the direction of gravity 36, terminatingat a further point. As the suspension system is compressed through itsdriven wheel suspension travel distance 15, change in measured squatdistance 13 over the driven wheel suspension travel distance 15 is usedto create a squat magnitude curve 17.

FIG. 2 b shows a side view of a shaft driven vehicle as shown in FIG. 2a with the driven wheel suspension system in a completely compressedstate. Certain embodiments are further exemplified, for example, vectorsuseful to a graphical method to attain a squat point measurement areshown. Also exemplified is a graphical method useful to attainsuspension geometry kinematical layout from an existing desired measuredsquat point. Shown in FIG. 2 b in addition to what is presented in FIG.2 a, are the following: first link fixed pivot (20); second link fixedpivot (21); first link floating pivot (22); second link floating pivot(23); instant force center (24); driven wheel rotation axis (25).

FIG. 2 b exemplifies that as the shaft driven wheel 1 suspension systemis completely compressed through its driven wheel suspension traveldistance 15, its defined squat force vector 7 moves in relation to thevehicle chassis 16. The squat force vector's 7 measured squat distance13 which is measured as the perpendicular distance between the lowersquat measurement definition line 12 and the squat definition point 10,decreases in relation to the measured squat distance 13 shown in FIG. 2a. This change in measured squat distance 13 over the driven wheelsuspension travel distance15 is used to create a squat magnitude curve17. FIG. 2 b shows the graphical method used to obtain a squat magnitudecurve 17 from shaft driven vehicle geometry, or shaft driven vehiclegeometry from a squat magnitude curve 17. In the vehicle shown in FIG. 2b, a driven wheel 1 is attached to a wheel carrier link2, which pivotsat one end of a first carrier manipulation link 3. The first carriermanipulation link 3 is pivotally attached to the vehicle chassis 16 atthe first link fixed pivot 20. A second carrier manipulation link 4 isalso attached to the wheel carrier link2. This second carriermanipulation link 4 is attached to the vehicle chassis 16 at a secondlink fixed pivot 21. A first carrier manipulation link force vector 8 isgraphed coincident to the wheel carrier link2 upper pivot and the firstlink fixed pivot 20. The first carrier manipulation link force vector 8is graphed so that it intersects a second carrier manipulation linkforce vector 9, which is graphed coincident to the wheel carrier link2lower pivot and the second link fixed pivot 21. The intersection pointof the first carrier manipulation link force vector 8 and the secondcarrier manipulation link force vector 9 is called the instant forcecenter 24. The squat force vector 7 is graphed from a beginning point atthe center of the driven wheel tire to ground contact patch 31, andpasses through the instant force center 24, before it terminates on asquat layout line 11. The intersection of the squat force vector 7 andthe squat layout line is called the squat layout point 10. The squatlayout line 11 is graphed at a perpendicular angle to gravitationalforce. A lower squat measurement definition line 12 is graphed beginningat the center of the driven wheel tire to ground contact patch 31 andterminating perpendicular and coincident to the squat layout line 11.The perpendicular measurement from the lower squat measurementdefinition line 12 to the squat layout point 10 is called the measuredsquat distance 13. This measured squat distance 13 changes as drivenwheel suspension travel distance 15 compresses, and is used to create asquat magnitude curve 17 in a squat magnitude curve graph as shown inFIG. 7 a, FIG. 7 b, FIG. 7 c, and FIG. 8.

FIG. 2 c shows an enlarged section of the side view of the shaft drivenvehicle shown in FIGS. 2 a and 2 b with the driven wheel suspensionsystem in a completely uncompressed state.

FIG. 2 d shows an enlarged section of the side view of the shaft drivenvehicle shown in FIGS. 2 a, 2 b, and 2 c with the driven wheelsuspension system in a completely compressed state. FIGS. 2 c and 2 dfurther exemplify certain embodiments, for example, points and vectorsuseful for a graphical method used to attain a squat point measurement,and a graphical method to attain suspension geometry kinematical layoutfrom an existing desired measured squat point.

FIG. 3 a shows certain embodiments of the invention relating to spindledriven vehicles and it presents a graphical method useful to attain asquat point measurement, and a graphical method to attain suspensiongeometry kinematical layout from an existing desired measured squatpoint. Shown in FIG. 3 a are the following: driven wheel (1); wheelcarrier link (2); first carrier manipulation link (3); second carriermanipulation link (4); driving force vector (6); squat force vector (7);first carrier manipulation link force vector (8); second carriermanipulation link force vector (9); squat definition point (10); squatlayout line (11); lower squat measurement definition line (12); measuredsquat distance (13); driven wheel axle path (14); driven wheelsuspension travel distance (15); vehicle chassis (16); driven wheelrotation axis (25); center of the forward wheel tire to ground contactpatch (30); center of the driven wheel tire to ground contact patch(31); direction of gravity (36).

FIG. 3 a exemplifies that as the driven wheel 1 suspension system iscompletely uncompressed in its driven wheel suspension travel distance15, its defined squat force vector 7 is shown in relation to the vehiclechassis 16. The squat force vector's 7 measured squat distance 13, whichis measured as the perpendicular distance between the lower squatmeasurement definition line 12 and the squat definition point 10, isshown in FIG. 3 a. The squat measurement definition line 12 begins atthe center of the driven wheel tire to ground contact patch 30, and isplotted parallel to and against the direction of gravity 36, terminatingat a further point. As the suspension system is compressed through itsdriven wheel suspension travel distance 15, change in measured squatdistance 13 over the driven wheel suspension travel distance 15 is usedto create a squat magnitude curve 17.

FIG. 3 b shows a side view of a spindle driven vehicle as shown in FIG.3 a with the driven wheel suspension system in a completely compressedstate. Certain embodiments are further exemplified, for example, vectorsuseful to a graphical method to attain a squat point measurement areshown. Also exemplified is a graphical method useful to attainsuspension geometry kinematical layout from an existing desired measuredsquat point. Shown in FIG. 3 b in addition to what is presented in FIG.3 a, are the following: first link fixed pivot (20); second link fixedpivot (21); first link floating pivot (22); second link floating pivot(23); instant force center (24).

FIG. 3 b exemplifies that as the spindle driven wheel 1 suspensionsystem is completely compressed through its driven wheel suspensiontravel distance 15, its defined squat force vector 7 moves in relationto the vehicle chassis 16. The squat force vector's 7 measured squatdistance 13 which is measured as the perpendicular distance between thelower squat measurement definition line 12 and the squat definitionpoint 10, decreases in relation to the measured squat distance 13 shownin FIG. 3 a. This change in measured squat distance 13 over the drivenwheel suspension travel distance15 is used to create a squat magnitudecurve 17. FIG. 3 b shows the graphical method used to obtain a squatmagnitude curve 17 from spindle driven vehicle geometry, or spindledriven vehicle geometry from a squat magnitude curve 17. In the vehicleshown in FIG. 3 b, a driven wheel 1 is attached to a wheel carrierlink2, which pivots at one end of a first carrier manipulation link 3.The first carrier manipulation link 3 is pivotally attached to thevehicle chassis 16 at the first link fixed pivot 20. A second carriermanipulation link 4 is also attached to the wheel carrier link2. Thissecond carrier manipulation link 4 is attached to the vehicle chassis 16at a second link fixed pivot 21. A first carrier manipulation link forcevector 8 is graphed coincident to the wheel carrier link2 upper pivotand the first link fixed pivot 20. The first carrier manipulation linkforce vector 8 is graphed so that it intersects a second carriermanipulation link force vector 9, which is graphed coincident to thewheel carrier link2 lower pivot and the second link fixed pivot 21. Theintersection point of the first carrier manipulation link force vector 8and the second carrier manipulation link force vector 9 is called theinstant force center 24. A driving force vector 6 is graphed from thedriven wheel rotation axis 25 through the instant force center 24. Thesquat force vector 7 is graphed from a beginning point at the drivenwheel rotation axis 25, and passes through the instant force center 24,before it terminates on a squat layout line 11. In a spindle drivenvehicle as shown in FIGS. 3 a-3 d, the driving force vector 6, and squatforce vector 7 are collinear with each other. The intersection of thesquat force vector 7 and the squat layout line is called the squatlayout point 10. The squat layout line 11 is graphed at a perpendicularangle to gravitational force. A lower squat measurement definition line12 is graphed beginning at the center of the driven wheel tire to groundcontact patch 31 and terminating perpendicular and coincident to thesquat layout line 11. The perpendicular measurement from the lower squatmeasurement definition line 12 to the squat layout point 10 is calledthe measured squat distance 13. This measured squat distance 13 changesas driven wheel suspension travel distance 15 compresses, and is used tocreate a squat magnitude curve 17 in a squat magnitude curve graph asshown in FIG. 7 a, FIG. 7 b, FIG. 7 c, and FIG. 8.

FIG. 3 c shows an enlarged section of the side view of the spindledriven vehicle shown in FIGS. 3 a and 3 b with the driven wheelsuspension system in a completely uncompressed state.

FIG. 3 d shows an enlarged section of the side view of the spindledriven vehicle shown in FIGS. 3 a, 3 b, and 3 c with the driven wheelsuspension system in a completely compressed state. FIGS. 3 c and 3 dfurther exemplify certain embodiments, for example, points and vectorsuseful for a graphical method used to attain a squat point measurement,and a graphical method to attain suspension geometry kinematical layoutfrom an existing desired measured squat point.

FIG. 4 a shows certain embodiments of the invention relating to chaindriven vehicles and it presents a graphical method useful to attain asquat point measurement, and a graphical method to attain suspensiongeometry kinematical layout from an existing desired measured squatpoint. Shown in FIG. 1 a are the following: driven wheel (1); wheelcarrier link (2); first carrier manipulation link (3); second carriermanipulation link (4); chain force vector (5); driving force vector (6);squat force vector (7); first carrier manipulation link force vector(8); second carrier manipulation link force vector (9); squat definitionpoint (10); squat layout line (11); lower squat measurement definitionline (12); measured squat distance (13); driven wheel axle path (14);driven wheel suspension travel distance (15); vehicle chassis (16);center of the forward wheel tire to ground contact patch (30); center ofthe driven wheel tire to ground contact patch (31); direction of gravity(36).

FIG. 4 a exemplifies that as the driven wheel 1 suspension system iscompletely uncompressed in its driven wheel suspension travel distance15; its squat force vector 7 is shown in relation to the vehicle chassis16. The squat force vector's 7 measured squat distance 13 which ismeasured as the perpendicular distance between the lower squatmeasurement definition line 12 and the squat definition point 10, isalso shown in FIG. 1 a. The squat measurement definition line 12 beginsat the center of the driven wheel tire to ground contact patch 30, andis plotted parallel to and against the direction of gravity 36,terminating at a further point. As the suspension system is compressedthrough its driven wheel suspension travel distance 15, change inmeasured squat distance 13 over the driven wheel suspension traveldistance15 is used to create a squat magnitude curve 17.

FIG. 4 b shows a side view of a chain driven vehicle as shown in FIG. 4a with the driven wheel suspension system in a completely compressedstate. Certain embodiments are further exemplified, for example, vectorsuseful to a graphical method to attain a squat point measurement areshown. Also exemplified is a graphical method useful to attainsuspension geometry kinematical layout from an existing desired measuredsquat point. Shown in FIG. 4 b in addition to what is presented in FIG.4 a, are the following: first link fixed pivot (20); second link fixedpivot (21); first link floating pivot (22); second link floating pivot(23); instant force center (24); driven wheel rotation axis (25); chainforce vector and driving force vector intersection point (26); drivingcog (27); driven cog (28); driving cog rotation axis (29).

FIG. 4 b exemplifies that as the driven wheel 1 suspension system iscompletely compressed through its driven wheel suspension traveldistance 15, its squat force vector 7 moves in relation to the vehiclechassis 16. The squat force vector's 7 measured squat distance 13, whichis measured as the perpendicular distance between the lower squatmeasurement definition line 12 and the squat definition point 10,decreases in relation to the measured squat distance 13 shown in FIG. 4a. This change in measured squat distance 13 over the driven wheelsuspension travel distance15, in certain preferred embodiments, is usedto create a squat magnitude curve 17. FIG. 4 b shows the graphicalmethod used to obtain a squat magnitude curve 17 from chain drivenvehicle geometry, or chain driven vehicle geometry from a squatmagnitude curve 17. In the vehicle shown in FIG. 1 b, a driven wheel 1is attached to a wheel carrier link2, which pivots at one end of a firstcarrier manipulation link 3. The first carrier manipulation link 3 ispivotally attached to the vehicle chassis 16 at the first link fixedpivot 20. A second carrier manipulation link 4 is also attached to thewheel carrier link2. This second carrier manipulation link 4 is attachedto the vehicle chassis 16 at a second link fixed pivot 21. A firstcarrier manipulation link force vector 8 is graphed coincident to thewheel carrier link2 upper pivot and the first link fixed pivot 20. Thefirst carrier manipulation link force vector 8 is graphed so that itintersects a second carrier manipulation link force vector 9, which isgraphed coincident to the wheel carrier link2 lower pivot and the secondlink fixed pivot 21. The intersection point of the first carriermanipulation link force vector 8 and the second carrier manipulationlink force vector 9 is called the instant force center 24. A drivingforce vector 6 is graphed beginning at the driven wheel rotation axis25, and passes through the instant force center 24. A chain force vector5 is drawn tangent to the tops of the driving cog 27 and driven cog 28,and intersects the driving force vector 6 at a chain force vector anddriving force vector intersection point 26. The squat force vector 7 isgraphed from a beginning point at the center of the driven wheel tire toground contact patch 31, and passes through the chain force vector anddriving force vector intersection point 26, before it terminates on asquat layout line 11. The intersection of the squat force vector 7 andthe squat layout line is called the squat layout point 10. The squatlayout line 11 is graphed at a perpendicular angle to gravitationalforce. A lower squat measurement definition line 12 is graphed beginningat the center of the driven wheel tire to ground contact patch 31 andterminating perpendicular and coincident to the squat layout line 11.The perpendicular measurement from the lower squat measurementdefinition line 12 to the squat layout point 10 is called the measuredsquat distance 13. This measured squat distance 13 changes as drivenwheel suspension travel distance 15 compresses, and is used to create asquat magnitude curve 17 in a squat magnitude curve graph as shown inFIG. 11 and FIG. 12.

FIG. 5 a shows certain embodiments of the invention relating to shaftdriven vehicles and it presents a graphical method useful to attain asquat point measurement, and a graphical method to attain suspensiongeometry kinematical layout from an existing desired measured squatpoint. Shown in FIG. 5 a are the following: driven wheel (1); wheelcarrier link (2); first carrier manipulation link (3); second carriermanipulation link (4); squat force vector (7); first carriermanipulation link force vector (8); second carrier manipulation linkforce vector (9); squat definition point (10); squat layout line (11);lower squat measurement definition line (12); measured squat distance(13); driven wheel axle path (14); driven wheel suspension traveldistance (15); vehicle chassis (16); instant force center (24); centerof the forward wheel tire to ground contact patch (30); center of thedriven wheel tire to ground contact patch (31); direction of gravity(36).

FIG. 5 a exemplifies that as the driven wheel 1 suspension system iscompletely uncompressed in its driven wheel suspension travel distance15, its defined squat force vector 7 is shown in relation to the vehiclechassis 16. The squat force vector's 7 measured squat distance 13, whichis measured as the perpendicular distance between the lower squatmeasurement definition line 12 and the squat definition point 10, isshown in FIG. 5 a. The squat measurement definition line 12 begins atthe center of the driven wheel tire to ground contact patch 30, and isplotted parallel to and against the direction of gravity 36, terminatingat a further point. As the suspension system is compressed through itsdriven wheel suspension travel distance 15, change in measured squatdistance 13 over the driven wheel suspension travel distance 15 is usedto create a squat magnitude curve 17.

FIG. 5 b shows a side view of a shaft driven vehicle as shown in FIG. 5a with the driven wheel suspension system in a completely compressedstate. Certain embodiments are further exemplified, for example, vectorsuseful to a graphical method to attain a squat point measurement areshown. Also exemplified is a graphical method useful to attainsuspension geometry kinematical layout from an existing desired measuredsquat point. Shown in FIG. 5 b in addition to what is presented in FIG.5 a, are the following: first link fixed pivot (20); second link fixedpivot (21); first link floating pivot (22); second link floating pivot(23); instant force center (24); driven wheel rotation axis (25).

FIG. 5 b exemplifies that as the shaft driven wheel 1 suspension systemis completely compressed through its driven wheel suspension traveldistance 15, its defined squat force vector 7 moves in relation to thevehicle chassis 16. The squat force vector's 7 measured squat distance13 which is measured as the perpendicular distance between the lowersquat measurement definition line 12 and the squat definition point 10,decreases in relation to the measured squat distance 13 shown in FIG. 5a. This change in measured squat distance 13 over the driven wheelsuspension travel distance15 is used to create a squat magnitude curve17. FIG. 5 b shows the graphical method used to obtain a squat magnitudecurve 17 from shaft driven vehicle geometry, or shaft driven vehiclegeometry from a squat magnitude curve 17. In the vehicle shown in FIG. 5b, a driven wheel 1 is attached to a wheel carrier link2, which pivotsat one end of a first carrier manipulation link 3. The first carriermanipulation link 3 is pivotally attached to the vehicle chassis 16 atthe first link fixed pivot 20. A second carrier manipulation link 4 isalso attached to the wheel carrier link2. This second carriermanipulation link 4 is attached to the vehicle chassis 16 at a secondlink fixed pivot 21. A first carrier manipulation link force vector 8 isgraphed coincident to the wheel carrier link2 upper pivot and the firstlink fixed pivot 20. The first carrier manipulation link force vector 8is graphed so that it intersects a second carrier manipulation linkforce vector 9, which is graphed coincident to the wheel carrier link2lower pivot and the second link fixed pivot 21. The intersection pointof the first carrier manipulation link force vector 8 and the secondcarrier manipulation link force vector 9 is called the instant forcecenter 24. The squat force vector 7 is graphed from a beginning point atthe center of the driven wheel tire to ground contact patch 31, andpasses through the instant force center 24, before it terminates on asquat layout line 11. The intersection of the squat force vector 7 andthe squat layout line is called the squat layout point 10. The squatlayout line 11 is graphed at a perpendicular angle to gravitationalforce. A lower squat measurement definition line 12 is graphed beginningat the center of the driven wheel tire to ground contact patch 31 andterminating perpendicular and coincident to the squat layout line 11.The perpendicular measurement from the lower squat measurementdefinition line 12 to the squat layout point 10 is called the measuredsquat distance 13. This measured squat distance 13 changes as drivenwheel suspension travel distance 15 compresses, and is used to create asquat magnitude curve 17 in a squat magnitude curve graph as shown inFIG. 7 a, FIG. 7 b, FIG. 7 c, and FIG. 8.

FIG. 6 a shows certain embodiments of the invention relating to spindledriven vehicles and it presents a graphical method useful to attain asquat point measurement, and a graphical method to attain suspensiongeometry kinematical layout from an existing desired measured squatpoint. Shown in FIG. 6 a are the following: driven wheel (1); wheelcarrier link (2); first carrier manipulation link (3); second carriermanipulation link (4); driving force vector (6); squat force vector (7);first carrier manipulation link force vector (8); second carriermanipulation link force vector (9); squat definition point (10); squatlayout line (11); lower squat measurement definition line (12); measuredsquat distance (13); driven wheel axle path (14); driven wheelsuspension travel distance (15); vehicle chassis (16); instant forcecenter (24); center of the forward wheel tire to ground contact patch(30); center of the driven wheel tire to ground contact patch (31);direction of gravity (36).

FIG. 6 a exemplifies that as the driven wheel 1 suspension system iscompletely uncompressed in its driven wheel suspension travel distance15, its defined squat force vector 7 is shown in relation to the vehiclechassis 16. The squat force vector's 7 measured squat distance 13, whichis measured as the perpendicular distance between the lower squatmeasurement definition line 12 and the squat definition point 10, isshown in FIG. 6 a. The squat measurement definition line 12 begins atthe center of the driven wheel tire to ground contact patch 30, and isplotted parallel to and against the direction of gravity 36, terminatingat a further point. As the suspension system is compressed through itsdriven wheel suspension travel distance 15, change in measured squatdistance 13 over the driven wheel suspension travel distance 15 is usedto create a squat magnitude curve 17.

FIG. 6 b shows a side view of a spindle driven vehicle as shown in FIG.6 a with the driven wheel suspension system in a completely compressedstate. Certain embodiments are further exemplified, for example, vectorsuseful to a graphical method to attain a squat point measurement areshown. Also exemplified is a graphical method useful to attainsuspension geometry kinematical layout from an existing desired measuredsquat point. Shown in FIG. 6 b in addition to what is presented in FIG.6 a, are the following: first link fixed pivot (20); second link fixedpivot (21); first link floating pivot (22); second link floating pivot(23); instant force center (24); driven wheel rotation axis (25).

FIG. 6 b exemplifies that as the spindle driven wheel 1 suspensionsystem is completely compressed through its driven wheel suspensiontravel distance 15, its defined squat force vector 7 moves in relationto the vehicle chassis 16. The squat force vector's 7 measured squatdistance 13 which is measured as the perpendicular distance between thelower squat measurement definition line 12 and the squat definitionpoint 10, decreases in relation to the measured squat distance 13 shownin FIG. 6 a. This change in measured squat distance 13 over the drivenwheel suspension travel distance15 is used to create a squat magnitudecurve 17. FIG. 6 b shows the graphical method used to obtain a squatmagnitude curve 17 from spindle driven vehicle geometry, or spindledriven vehicle geometry from a squat magnitude curve 17. In the vehicleshown in FIG. 6 b, a driven wheel 1 is attached to a wheel carrierlink2, which pivots at one end of a first carrier manipulation link 3.The first carrier manipulation link 3 is pivotally attached to thevehicle chassis 16 at the first link fixed pivot 20. A second carriermanipulation link 4 is also attached to the wheel carrier link2. Thissecond carrier manipulation link 4 is attached to the vehicle chassis 16at a second link fixed pivot 21. A first carrier manipulation link forcevector 8 is graphed coincident to the wheel carrier link2 upper pivotand the first link fixed pivot 20. The first carrier manipulation linkforce vector 8 is graphed so that it intersects a second carriermanipulation link force vector 9, which is graphed coincident to thewheel carrier link2 lower pivot and the second link fixed pivot 21. Theintersection point of the first carrier manipulation link force vector 8and the second carrier manipulation link force vector 9 is called theinstant force center 24. A driving force vector 6 is graphed from thedriven wheel rotation axis 25 through the instant force center 24. Thesquat force vector 7 is graphed from a beginning point at the drivenwheel rotation axis 25, and passes through the instant force center 24,before it terminates on a squat layout line 11. In a spindle drivenvehicle as shown in FIGS. 3 a-3 d, the driving force vector 6, and squatforce vector 7 are collinear with each other. The intersection of thesquat force vector 7 and the squat layout line is called the squatlayout point 10. The squat layout line 11 is graphed at a perpendicularangle to gravitational force. A lower squat measurement definition line12 is graphed beginning at the center of the driven wheel tire to groundcontact patch 31 and terminating perpendicular and coincident to thesquat layout line 11. The perpendicular measurement from the lower squatmeasurement definition line 12 to the squat layout point 10 is calledthe measured squat distance 13. This measured squat distance 13 changesas driven wheel suspension travel distance 15 compresses, and is used tocreate a squat magnitude curve 17 in a squat magnitude curve graph asshown in FIG. 7 a, FIG. 7 b, FIG. 7 c, and FIG. 8.

FIG. 7 a shows a stable squat magnitude curve (17) for suspensionsystems according to certain embodiments of the invention graphed on asquat magnitude curve graph as disclosed herein. The percent of totalsuspension travel (i.e., percent total travel) is shown on the x-axis,and the percent of total squat (i.e., percent squat magnitude) is shownon the y-axis. The stable squat magnitude curve 17 shown in FIG. 7 adisplays an average value of approximately one-hundred percent antisquat.

FIG. 7 b shows a stable squat magnitude curve 17 for suspension systemsaccording to certain embodiments of the invention graphed on a squatmagnitude curve graph as disclosed herein. The percent of totalsuspension travel is shown on the x-axis, and the percent of total squatis shown on the y-axis. The stable squat magnitude curve 17 shown inFIG. 7 a displays an average value of approximately fifty percent antisquat.

FIG. 7 c shows a closer view of the stable squat magnitude curve 17 forsuspension systems according to certain embodiments of the inventiongraphed on a squat magnitude curve graph as disclosed herein and asshown in FIG. 7 a. The percent of total suspension travel is shown onthe x-axis, and the percent of total squat is shown on the y-axis. Thestable squat magnitude curve 17 shown in FIG. 7 a displays an averagevalue of approximately one-hundred percent anti squat. The stable squatmagnitude curve 17 defines a squat magnitude curve upper bound (18), asquat magnitude curve lower bound (19), and a percent squat magnitudevariation (41).

FIG. 8 shows a squat magnitude curve for suspension systems according tocertain embodiments of the invention. The percent of total suspensiontravel is shown on the x-axis, and the percent of total squat is shownon the y-axis. FIG. 8 exemplifies a squat magnitude curve 17 withtangent lines depicting a slope of the curve at certain points along thesquat magnitude curve. The slopes exemplified by the tangent lines are afirst squat magnitude curve slope (42), a second squat magnitude curveslope (43), a third squat magnitude curve slope (44). FIG. 8 exemplifiesa slope of the squat magnitude curve 17 as produced by a suspensionsystem of certain embodiments of the current invention, for example, asuspension system including features as illustrated in FIGS. 2 a-2 d andFIGS. 5 a and 14 d, and that the slope varies as the vehicle suspensiontravel distance increases. The squat magnitude curve 17 produced has afirst squat magnitude curve slope 42 that has a positive value at thebeginning point in the suspension travel, and a second squat magnitudecurve slope 43 at an interim point that has a negative value, and athird squat magnitude curve slope 44 at the ending point in thesuspension travel that has a positive value.

FIG. 9 shows a stable squat magnitude curve 17 for suspension systemsaccording to certain embodiments of the invention for example, asuspension system including features as illustrated in FIGS. 1 a-1 d,graphed on a squat magnitude curve graph as disclosed herein. Thepercent of total suspension travel is shown on the x-axis, and thepercent of total squat is shown on the y-axis

FIG. 10 shows a closer view of the stable squat magnitude curve 17 forsuspension systems according to certain embodiments of the inventiongraphed on a squat magnitude curve graph as disclosed herein and asshown in FIG. 9. The percent of total suspension travel is shown on thex-axis, and the percent of total squat is shown on the y-axis. Thestable squat magnitude curve 17 shown in FIG. 10 displays an averagevalue of approximately one-hundred percent anti squat. The stable squatmagnitude curve 17 defines a squat magnitude curve upper bound (18), asquat magnitude curve lower bound (19), and a percent squat magnitudevariation (41).

FIG. 11 shows a stable squat magnitude curve 17 for suspension systemsaccording to certain embodiments of the invention for example, asuspension system including features as illustrated in FIGS. 4 a and 4b, graphed on a squat magnitude curve graph as disclosed herein. Thepercent of total suspension travel is shown on the x-axis, and thepercent of total squat is shown on the y-axis

FIG. 12 shows a closer view of the stable squat magnitude curve 17 forsuspension systems according to certain embodiments of the inventiongraphed on a squat magnitude curve graph as disclosed herein and asshown in FIG. 11. The percent of total suspension travel is shown on thex-axis, and the percent of total squat is shown on the y-axis. Thestable squat magnitude curve 17 shown in FIG. 12 displays an averagevalue of approximately one-hundred percent anti squat. The stable squatmagnitude curve 17 defines a squat magnitude curve upper bound (18), asquat magnitude curve lower bound (19), and a percent squat magnitudevariation (41).

FIG. 13 shows an instant force center 24 which is described by a linkagesystem for controlling a driven wheel axle path 14. The instant forcecenter 24 travels on an instant force center path 45 with an approximateinstant force center path focus (46). A suspension layout as shown inFIGS. 1 a,1 b,1 c,1 d, 4 a, and 4 b can produce an instant force centerpath 45. This instant force center path focus 46 may traverse distancesduring the driven wheel suspension travel distance 15. The instant forcecenter path 45 has an instant force center path focus 46 located withinthe pitch diameter (47) of a driving cog 27 for a percentage of thedriven wheel suspension travel distance 15.

FIG. 14 presents a graphical method useful to attain a squat magnitudedefinition point location, and a graphical method to attain a squatmagnitude definition point location from existing measured or planneddesired vehicle geometry. Shown in FIG. 14 are the following: drivenwheel (1); squat layout line (11); lower squat measurement definitionline (12); vehicle chassis (16); center of the driven wheel tire toground contact patch (31); vehicle center of sprung mass (32); 200percent squat point (33); 200 percent measurement value (34); forwardwheel (35); direction of gravity (36); squat magnitude definition point(37); squat magnitude (38); center of mass intersection vector (39);squat magnitude definition vector (40).

FIG. 14 exemplifies graphing the vehicle center of sprung mass 32 inrelation to the vehicle chassis 16. A center of mass intersection vector39 is drawn from the center of the driven wheel tire to ground contactpatch 31, through the center of sprung mass 32, and terminating on thesquat layout line 11. The point at which the center of mass intersectionvector 39 meets the squat layout line 11 is defined as the 200 percentsquat point 33. The distance between the 200 percent squat point 33 andthe squat lower measurement definition line12 is referred to as the 200percent measurement value 34. This 200 percent measurement value 34 isused as a reference to determine squat magnitude 38 value. The distancebetween the graphed squat magnitude definition point 37 and the squatlower measurement definition line 12 is referred to as the squatmeasurement definition value 37. Both the 200 percent squat point 33 andthe squat measurement definition value 37 are graphed on the squatlayout line 11.

FIG. 15 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 1 a which can produce the squat magnitude curve 17of the invention.

FIG. 16 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 1 a which can produce the squat magnitude curve 17of the invention.

FIG. 17 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 1 a which can produce the squat magnitude curve 17of the invention.

FIG. 18 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 1 a which can produce the squat magnitude curve 17of the invention.

FIG. 19 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 1 a which can produce the squat magnitude curve 17of the invention.

FIG. 20 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 2 a which can produce the squat magnitude curve 17of the invention.

FIG. 21 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 2 a which can produce the squat magnitude curve 17of the invention.

FIG. 22 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 2 a which can produce the squat magnitude curve 17of the invention.

FIG. 23 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 2 a which can produce the squat magnitude curve 17of the invention.

FIG. 24 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 2 a which can produce the squat magnitude curve 17of the invention.

FIG. 25 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 2 a which can produce the squat magnitude curve 17of the invention.

FIG. 26 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 2 a which can produce the squat magnitude curve 17of the invention.

FIG. 27 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 4 a which can produce the squat magnitude curve 17of the invention.

FIG. 28 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 4 a which can produce the squat magnitude curve 17of the invention.

FIG. 29 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 4 a which can produce the squat magnitude curve 17of the invention.

FIG. 30 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 4 a which can produce the squat magnitude curve 17of the invention.

FIG. 31 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 4 a which can produce the squat magnitude curve 17of the invention.

FIG. 32 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 4 a which can produce the squat magnitude curve 17of the invention.

FIG. 33 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 5 a which can produce the squat magnitude curve 17of the invention.

FIG. 34 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 5 a which can produce the squat magnitude curve 17of the invention.

FIG. 35 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 5 a which can produce the squat magnitude curve 17of the invention.

FIG. 36 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 5 a which can produce the squat magnitude curve 17of the invention.

FIG. 37 illustrates the possible placement of a damper unit (50) in avehicle with the chain driven vehicle suspension layout as firstillustrated in FIG. 5 a which can produce the squat magnitude curve 17of the invention.

FIG. 38 shows a variation on the chain driven vehicle shown in FIG. 4,where a driven idler cog (48) is represented by its driven idler cogpitch diameter, and rotates around a driven idler cog rotation axis (49)which is fixed to a vehicle chassis 16. The chain force vector 6direction is controlled by the driven idler cog 48, and therefore,vehicle suspension geometry must be altered to achieve the desired squatmagnitude curve 17. Also shown is a spring damper unit (50).

FIG. 39 illustrates a sliding element type shaft driven or spindledriven suspension system of the invention and it presents a graphicalmethod useful to determine instant force center movement. Shown in FIG.39 are the following: driven wheel (1); wheel carrier link (2); lowersquat measurement definition line (12); driven wheel axle path (14);driven wheel suspension travel distance (15); vehicle chassis (16);instant force center (24); driven wheel rotation axis (25); center ofthe forward wheel tire to ground contact patch (30); center of thedriven wheel tire to ground contact patch (31); direction of gravity(36); first carrier manipulation track (51); second carrier manipulationtrack (52); first carrier manipulation slider (53); second carriermanipulation slider (54); first carrier manipulation slider force vector(55); second carrier manipulation slider force vector (56); firstcarrier manipulation slider pivot (69); second carrier manipulationslider pivot (70)

FIG. 39 shows a sliding element type suspension layout in anuncompressed state. A sliding element type suspension layout can containa first carrier manipulation track 51 and a second carrier manipulationtrack 52. The first carrier manipulation track 51 and second carriermanipulation track 52 can be straight linear, or curved in shape. Afirst carrier manipulation slider 53 rides on the first carriermanipulation track 51 and the second carrier manipulation slider 54rides on the second carrier manipulation track 52 so that the eachslider's motion is defined by following the path of the track. A wheelcarrier link 2 is pivotally attached to the first carrier manipulationslider 53 and second carrier manipulation slider 54 so that movement ofthe wheel carrier link is governed by movement of the first carriermanipulation slider 53 and second carrier manipulation slider 54. Thefirst carrier manipulation slider 53 projects a first carriermanipulation slider force vector 55, which is projected perpendicular tothe path of the track at the center of the first carrier manipulationslider pivot 69. The second carrier manipulation slider 54 projects asecond carrier manipulation slider force vector 56, which is projectedperpendicular to the path of the track from the center of the secondcarrier manipulation slider pivot 70. The intersection of the firstcarrier manipulation slider force vector 55 and second carriermanipulation slider force vector 56 describes the location of an instantforce center 24. As the driven wheel 1 moves compressively through itsdriven wheel suspension travel distance 15, its instant center movesalong an instant force center path 45.

FIG. 40 illustrates a sliding element type shaft driven or spindledriven suspension system of the invention and it presents a graphicalmethod useful to determine instant force center movement. Shown in FIG.39 are the following: driven wheel (1); wheel carrier link (2); lowersquat measurement definition line (12); driven wheel axle path (14);driven wheel suspension travel distance (15); vehicle chassis (16);instant force center (24); driven wheel rotation axis (25); center ofthe forward wheel tire to ground contact patch (30); center of thedriven wheel tire to ground contact patch (31); direction of gravity(36); first carrier manipulation track (51); second carrier manipulationtrack (52); first carrier manipulation slider (53); second carriermanipulation slider (54); first carrier manipulation slider force vector(55); second carrier manipulation slider force vector (56); firstcarrier manipulation slider pivot (69); second carrier manipulationslider pivot (70)

FIG. 40 shows a sliding element type suspension layout in a compressedstate. A sliding element type suspension layout can contain a firstcarrier manipulation track 51 and a second carrier manipulation track52. The first carrier manipulation track 51 and second carriermanipulation track 52 can be straight linear, or curved in shape. Afirst carrier manipulation slider 53 rides on the first carriermanipulation track 51 and the second carrier manipulation slider 54rides on the second carrier manipulation track 52 so that the eachslider's motion is defined by following the path of the track. A wheelcarrier link 2 is pivotally attached to the first carrier manipulationslider 53 and second carrier manipulation slider 54 so that movement ofthe wheel carrier link is governed by movement of the first carriermanipulation slider 53 and second carrier manipulation slider 54. Thefirst carrier manipulation slider 53 projects a first carriermanipulation slider force vector 55, which is projected perpendicular tothe path of the track at the center of the first carrier manipulationslider pivot 69. The second carrier manipulation slider 54 projects asecond carrier manipulation slider force vector 56, which is projectedperpendicular to the path of the track from the center of the secondcarrier manipulation slider pivot 70. The intersection of the firstcarrier manipulation slider force vector 55 and second carriermanipulation slider force vector 56 describes the location of an instantforce center 24. As the driven wheel 1 moves compressively through itsdriven wheel suspension travel distance 15, its instant center movesalong an instant force center path 45.

FIG. 41 illustrates a sliding element type shaft driven or spindledriven suspension system of the invention and it presents a graphicalmethod useful to determine instant force center movement. Shown in FIG.39 are the following: driven wheel (1); wheel carrier link (2); lowersquat measurement definition line (12); driven wheel axle path (14);driven wheel suspension travel distance (15); vehicle chassis (16);instant force center (24); driven wheel rotation axis (25); center ofthe forward wheel tire to ground contact patch (30); center of thedriven wheel tire to ground contact patch (31); direction of gravity(36); first carrier manipulation track (51); second carrier manipulationtrack (52); first carrier manipulation slider (53); second carriermanipulation slider (54); first carrier manipulation slider force vector(55); second carrier manipulation slider force vector (56); instantforce center position uncompressed (65); instant force center positioncompressed (66); first carrier manipulation slider pivot (69); secondcarrier manipulation slider pivot (70)

FIG. 41 shows a sliding element type suspension layout in anuncompressed state shown in FIG. 39 overlaid with the sliding elementtype suspension layout in an compressed state shown in FIG. 40. Asliding element type suspension layout can contain a first carriermanipulation track 51 and a second carrier manipulation track 52. Thefirst carrier manipulation track 51 and second carrier manipulationtrack 52 can be straight linear, or curved in shape. A first carriermanipulation slider 53 rides on the first carrier manipulation track 51and the second carrier manipulation slider 54 rides on the secondcarrier manipulation track 52 so that the each slider's motion isdefined by following the path of the track. A wheel carrier link 2 ispivotally attached to the first carrier manipulation slider 53 andsecond carrier manipulation slider 54 so that movement of the wheelcarrier link is governed by movement of the first carrier manipulationslider 53 and second carrier manipulation slider 54. The first carriermanipulation slider 53 projects a first carrier manipulation sliderforce vector 55, which is projected perpendicular to the path of thetrack at the center of the first carrier manipulation slider pivot 69.The second carrier manipulation slider 54 projects a second carriermanipulation slider force vector 56, which is projected perpendicular tothe path of the track from the center of the second carrier manipulationslider pivot 70. The intersection of the first carrier manipulationslider force vector 55 and second carrier manipulation slider forcevector 56 describes the location of an instant force center 24. As thedriven wheel 1 moves compressively through its driven wheel suspensiontravel distance 15, its instant center moves along an instant forcecenter path 45. As the driven wheel 1 moves compressively through itsdriven wheel suspension travel distance 15, its instant center 24 movesfrom an instant force center position uncompressed 65 to an instantforce center position compressed 66.

FIG. 42 shows certain embodiments of the invention and it presents agraphical method useful to determine instant force center movement. FIG.42 uses components and a chassis layout first shown in FIGS. 2 a, 2 b, 2c, 2 d, 3 a, 3 b, 3 c, and 3 d. Shown in FIG. 42 are the following:driven wheel (1); lower squat measurement definition line (12); drivenwheel axle path (14); driven wheel suspension travel distance (15);vehicle chassis (16); driven wheel rotation axis (25); center of theforward wheel tire to ground contact patch (30); center of the drivenwheel tire to ground contact patch (31); direction of gravity (36);first carrier manipulation link force vector uncompressed (61); secondcarrier manipulation link force vector uncompressed (62); first carriermanipulation link force vector compressed (63); second carriermanipulation link force vector compressed (64); instant force centerposition uncompressed (65); instant force center position compressed(66); instant force center upward movement (67); instant force centerrearward movement (68).

FIG. 42 exemplifies that as the driven wheel 1 suspension system iscompletely uncompressed in its driven wheel suspension travel distance15, its layout projects a first carrier manipulation link force vectoruncompressed 61 and a second carrier manipulation slider force vectoruncompressed 62, which intersect at an instant force center positionuncompressed 65. As the driven wheel 1 suspension moves compressivelythrough its driven wheel suspension travel distance 15, its layoutprojects a first carrier manipulation link force vector compressed 63and a second carrier manipulation slider force vector compressed 64,which intersect at an instant force center position compressed 66. Asthe driven wheel 1 moves compressively through its driven wheelsuspension travel distance 15, its instant center moves from an instantforce center position uncompressed 65 to an instant force centerposition compressed 66. A suspension of the invention has a measurableinstant force center upward movement 67; or a measurable instant forcecenter rearward movement 68; or a combination of a measurable instantforce center upward movement 67 and a measurable instant force centerrearward movement 68. The instant force center upward movement 67 ismeasured with the vehicle at rest on level ground, against the directionof gravity 36, starting at the instant force center positionuncompressed 65, and measured to an instant force center positioncompressed 66. The instant force center rearward movement 68 is measuredwith the vehicle at rest on level ground, perpendicular the direction ofgravity 36, starting at the instant force center position uncompressed65, and measured to an instant force center position compressed 66.

A vehicle using a suspension of the invention may, in certainembodiments, comprise a squat magnitude curve, a measurable suspensionparameter, vehicle metrics, a frame, a moving suspension component, apivot, a rotary motion device, a motion control device, and/or apower-train component. A squat magnitude curve, according to certainembodiments, may be comprised of a measured curve, a graph, a graphedcurve, a plotted curve, a line, a curves, a value, varying values, fixedvalues, varying curve, amplitude, frequency, value, squat magnitude,magnitude, squat, pro squat, anti squat, zero squat, slope, slopes,varying slope, fixed slope, negative slope, first negative slope, secondnegative slope, third negative slope, fourth negative slope, fifthnegative slope, sixth negative slope, seventh negative slope, eightnegative slope, ninth negative slope, tenth negative slope, eleventhnegative slope, positive slope, first positive slope, second positiveslope, third positive slope, fourth positive slope, fifth positiveslope, sixth positive slope, seventh positive slope, eight positiveslope, ninth positive slope, tenth positive slope, eleventh positiveslope, negative value, positive value, varying rise, rise, beginningrise, interim rise, ending rise, beginning slope, interim slope, firstinterim slope, second interim slope, third interim slope, fourth interimslope, fifth interim slope, sixth interim slope, seventh interim slope,eighth interim slope ninth interim slope, tenth interim slope, eleventhinterim slope, ending slope, final slope, infinitely varying slope,constantly varying slope, controlled slope, tuned slope, tunedamplitude, tuned frequency, variable squat magnitude, variable squatcurve slope, tuned squat curve slope, and/or a controlled squat curveslope.

A measurable suspension parameter and vehicle metrics, in certainembodiments, may comprise a wheelbase, track width, camber, caster, antisquat, pro squat, zero squat, squat, rake, trail, offset, fork offset,spindle offset, chainstay length, swingarm length, distance betweendriven wheel rotation axis and power unit output spindle axis, chainlength, belt length, bottom bracket, bottom bracket offset, drivespindle, drive spindle offset, drive spindle height, wheel diameter,driven wheel diameter, driven wheel spindle height, chainstay slope,chainstay rise, center of mass, center of mass height, center of massoffset, center of mass offset from drive spindle, length, magnitude, toptube length, downtube length, front center distance, seat tube length,seatstay length, headset stack height, head tube angle, fork angle,impact angle, fork rake, crown rake, handlebar height, bar height, barsweep, handlebar sweep, handlebar rise, bar rise, crank length, crankarm length, pitch diameter, gear pitch diameter, sprocket pitchdiameter, cog pitch diameter, front gear pitch diameter, front sprocketpitch diameter, front cog pitch diameter, rear gear pitch diameter, rearsprocket pitch diameter, rear cog pitch diameter, first intermediategear pitch diameter, second intermediate gear pitch diameter, firstintermediate sprocket pitch diameter, second intermediate sprocket pitchdiameter, first intermediate cog pitch diameter, second intermediate cogpitch diameter, instant center, instant force center, center ofcurvature, axle path, axle path center of curvature, moving center ofcurvature, forward moving center of curvature, forward moving instantcenter, rearward moving instant center, instant center movementdirection change, center of curvature path, instant center path, instantcenter path focus, moving instant center path focus, virtual forcecenter, virtual instant force center, virtual force center path, drivingforce, chain force, anti rotation force, sprocket force, bevel gearforce, rotational force, driving force vector, chain pull, chain pullforce, chain pull force vector, idler gear height, idler gear pitchdiameter, idler cog pitch diameter, idler sprocket pitch diameter,jackshaft gear pitch diameter, jackshaft cog pitch diameter, jackshaftsprocket pitch diameter, leverage rate, leverage ratio, damper leveragerate, damper leverage ratio, spring leverage rate, spring leverageratio, wheel motion ratio, wheel rate, spring rate, damping rate,leverage rate progression curve, leverage rate progression, progressiverate, regressive rate, straight rate, varying rate, suspensioncompression, full suspension compression, suspension extension, fullsuspension extension, droop travel, full droop travel, suspension rideheight, static ride height, neighed ride height, laden ride height,weighted ride height, beginning of travel, middle of travel, end oftravel, 0 percent travel to 20 percent travel, 20 percent travel to 80percent travel, 80 percent travel to 100 percent travel, 0 percenttravel to 25 percent travel, 25 percent travel to 75 percent travel, 75percent travel to 100 percent travel, 0 percent travel to 30 percenttravel, 30 percent travel to 65 percent travel, 65 percent travel to 100percent travel, 0 percent travel to 35 percent travel, 35 percent travelto 60 percent travel, 60 percent travel to 100 percent travel,powertrain component rotation axis, driven wheel rotation axis, nondriven wheel rotation axis, sprocket rotation axis, axis, axis location,rear wheel rotation axis, front wheel rotation axis, contact patch, tirecontact patch, tire to ground contact patch, driven wheel tire to groundcontact patch, non driven wheel tire to ground contact patch, frontwheel tire to ground contact patch, rear wheel tire to ground contactpatch, chain force vector, driving force vector, squat force vector,first carrier manipulation link force vector, second carriermanipulation link force vector, squat definition point, squat layoutline, lower squat measurement definition line, measured squat distance,driven wheel axle path, driven wheel suspension travel distance, stablesquat magnitude curve, defines a squat magnitude curve upper bound, asquat magnitude curve lower bound, instant force center, driven wheelrotation axis, chain force vector and driving force vector intersectionpoint, driving cog rotation axis, center of the forward wheel tire toground contact patch, center of the driven wheel tire to ground contactpatch, vehicle center of sprung mass, 200 percent squat point, 200percent measurement value, direction of gravity, squat magnitudedefinition point, squat magnitude, center of mass intersection vector,squat magnitude definition vector, percent squat magnitude variation,first squat magnitude curve slope, first squat magnitude curve slope,second squat magnitude curve slope, third squat magnitude curve slope,instant force center path, instant force center path focus, pitchdiameter, driven idler cog rotation axis, first carrier manipulationslider force vector, second carrier manipulation slider force vector,first carrier manipulation slider force vector uncompressed, secondcarrier manipulation slider force vector uncompressed, first carriermanipulation slider force vector compressed, second carrier manipulationslider force vector compressed, first carrier manipulation link forcevector uncompressed, second carrier manipulation link force vectoruncompressed, first carrier manipulation link force vector compressed,second carrier manipulation link force vector compressed, instant forcecenter position uncompressed, instant force center position compressed,instant force center upward movement, and/or an instant force centerrearward movement.

A frame, in certain embodiments, may be comprised of a solid beam, asolid bar, a metal bar, a plastic bar, a composite bar, a tube, a metaltube, an aluminum tube, a titanium tube, a steel tube, a composite tube,a carbon tube, a boron tube, an alloy tube, a magnesium tube, a stifftube, a flexible tube, a thin walled tube, a thick walled tube, a buttedtube, a single butted tube, a double butted tube, a triple butted tube,a quadruple butted tube, a straight gage tube, a round tube, a squaretube, a rectangular tube, a rounded corner tube, a shaped tube, an aerotube, a streamline tube, a plus shaped tube, a bat shaped tube, a tubethat transitions from a round tube to a rectangular tube, a tube thattransitions from a round tube to a square tube, a tube that transitionsfrom a round tube to a rounded corner tube, a tube that transitions froma round tube to a shaped tube, welding, MIG welding, TIG welding, laserwelding, friction welding, a welded tube, a TIG welded tube, a MIGwelded tube, a laser welded tube, a friction welded tube, a monocoquesection, a monocoque frame, metal monocoque, TIG welded monocoque, MIGwelded monocoque, laser welded monocoque, friction welded monocoque,carbon monocoque, Kevlar monocoque, fiberglass monocoque, compositemonocoque, fiberglass, carbon fiber, foam, honeycomb, stress skin,braces, extrusion, extrusions, metal inserts, rivets, screws, castings,forgings, CNC machined parts, machined parts, stamped metal parts,progressive stamped metal parts, tubes or monocoque parts welded to castparts, tubes or monocoque parts welded to forged parts, tubes ormonocoque parts welded to machined parts, tubes or monocoque partswelded to CNC machined parts, glue, adhesive, acrylic adhesive,methacrylate adhesive, bonded panels, bonded tubes, bonded monocoque,bonded forgings, bonded castings, tubes bonded to CNC machined parts,tubes bonded to machined parts, tubes bonded to castings, tubes bondedto forgings, gussets, supports, support tubes, tabs, bolts, tubes weldedto tabs, monocoque welded to tabs, tubes bolted to tabs, injectionmolded parts, seatstays, chainstays, a seatstay, a chainstay, a seattube, seat tower, seatpost, seat, top tube, upper tube, downtube, lowertube, top tubes, down tubes, seat tube brace, and/or a seat tubesupport.

A moving suspension component of a suspension system of the invention,according to certain embodiments, may be comprised of a link, a wheelcarrier link, a wheel carrier, a carrier manipulation link, an uppercarrier manipulation link, lower carrier manipulation link, firstcarrier manipulation link, second carrier manipulation link, swingarm,swingarms swinging arm, swinging arms, swing link, swing links, firstlink, second link, upper link, lower link, top link, bottom link,forward link, rearward link, front link, back link, primary link,secondary link, flexure, flexures, first flexure, second flexure, upperflexure, lower flexure, top flexure, bottom flexure, forward flexure,rearward flexure, front flexure, back flexure, primary flexure,secondary flexure, carrier manipulation flexures, sliders, curvedsliders, straight sliders, complex curved sliders, carriers, tracks,curved tracks, straight tracks, complex curved tracks, bearings, cams,gears, seals, pivots, shock link, linkages, shock driving links, A-Arms,H-Arms, support arms, upper support, lower support, double arms, singlearms, single pivot, multi pivot, SLA, Short Long Arm, hub carrier, wheelcarrier, spindle, spindle carrier, wheel support, spindle support,trailing arm, semi-trailing arm, swingarm, double swingarm, parallellinks, semi-parallel links, perpendicular links, strut, MacPhersonstrut, suspension strut, linear bearing, linear bushing, stanchion,fork, fork lower, 4-bar linkage, 5-bar linkage, 6-bar linkage, 7 barlinkage, 8 bar linkage, linkage, multi link, trackbar, panhard bar,watts link, watt link, ball joints, heim joint, radial joint, rotaryjoint, internal damper, external damper, enclosed damper, enclosedspring, caster block, camber block, caster wedge, driven wheel, vehiclechassis, first link fixed pivot, second link fixed pivot, first linkfloating pivot, second link floating pivot, driving cog, driven cog,forward wheel, driven idler cog, spring damper unit, first carriermanipulation track, second carrier manipulation track, first carriermanipulation slider, second carrier manipulation slider, first carriermanipulation slider pivot, second carrier manipulation slider pivot,stiffening link, and/or a stiffening linkage.

A pivot and a rotary motion devices of a suspension of the invention,according to certain embodiments, may be comprised of a pivot, a mainpivot, a chainstay pivot, a seatstay pivot, an upper main pivot, a lowerframe pivot, an upper frame pivot, a bottom frame pivot, a top framepivot, a forward frame pivot, a rearward frame pivot, a front framepivot, a rear frame pivot, a primary frame pivot, a secondary framepivot, a tertiary frame pivot, a first frame pivot, a second framepivot, a third frame pivot, a fourth frame pivot, combinations ofpivots, bearing pivots, bushing pivots, bearings, bushings, seals,grease ports, greased pivots, oiled pivots, needle bearing pivots,journal bearing pivots, DU bearing pivots, plastic bushing pivots,plastic bearing pivots, aluminum pivot shafts, stainless steel pivotshafts, steel pivot shafts, titanium pivot shafts, plastic pivot shafts,composite pivot shafts, hardened bearing races, hardened pivot shafts,anodized pivot shafts, plated pivot shafts, coated pivot shafts, bearingcaps, bearings seals, o-rings, o-ring seals, x-rings, and/or a x-ringseal.

A motion control device of a suspension of the invention, according tocertain embodiments, may be comprised of a shock, a shock absorber, aspring damper unit, a damper, a spring, a coil spring, a leaf spring, acompression spring, an extension spring, an air spring, a nitrogenspring, a gas spring, a torsion spring, a constant force spring, a flatspring, a wire spring, a carbon spring, a negative spring, a positivespring, a progressive spring, multiple springs, stacked springs, springsin series, springs in parallel, springs separate from a damper unit, adamper unit, hydraulics, hydraulic pistons, hydraulic valves, airvalves, air cans, gears, cams, a cam, a gear, noncircular gears, lineardamper, rotary damper, vane damper, friction damper, poppet valve,compensation spring, negative spring, elastomer, rubber bumper, bumper,progressive bumper, hydraulic bottoming bumper, pressure compensation,heat compensation, oil, water, damping fluid, cooling fluid, shims,pressure, shaft, through shaft, eyelet, adjusters, compensator, hose,reservoir, remote reservoir, low speed adjuster, high speed adjuster,mid range adjuster, bypass circuit, foot valve, large bump adjuster,small bump adjuster, high velocity adjuster, low velocity adjuster,hydraulic ram, hydraulic piston, active suspension, and/or amicroprocessor.

A powertrain component of a suspension of the invention, according tocertain embodiments, may be comprised of an energy storage device, abattery, fuel, a fuel tank, a flywheel, a liquid fuel, solid fuel,rocket fuel, a reactor, steam, a nuclear reactor, a fusion reactor,pressure, air pressure, hydraulic pressure, gas pressure, expanding gas,a motor, an electric motor, a hydraulic motor, a turbine motor, a steamturbine, a gas turbine motor, an engine, a gasoline engine, a dieselengine, diesel, gasoline, alcohol, sterling engine, a two stroke engine,a four stroke engine, miller cycle engine, ramjet engine, turbineengine, rocket engine, human power, horse power, animal power, potentialenergy, spring, compression spring, extension spring, constant forcespring, progressive spring, power transfer components, wire, rope,string, chain, belt, shaft, gear, cog, cam, sprocket, pulley, lever,clutch, one way clutch, one way bearing, bearing, ball bearing, journalbearing, bushing, drive sprocket, driven sprocket, drive cog, drivencog, drive gear, driven gear, intermediate cog, intermediate sprocket,intermediate gear, idler cog, idler sprocket, idler gear, bottombracket, bottom bracket spindle, crank arm, foot pedal, pedal, handcrank, cassette, sprocket cluster, derailleur, front derailleur, rearderailleur, chainguide, single ring chainguide, dual ring chainguide,multi ring chainguide, shifter, shift lever, shifter cable, shifterhose, hydraulic shifting, air shifting, pneumatic shifting, gearbox,transmission, continuously variable transmission, infinitely variabletransmission, direct drive, tire, wheel, track, track segment, idlerwheel, jet, driving cog, driven cog, forward wheel, driven idler cog.

Mass transfer is discussed. All vehicles have mass. Mass in all vehicleswith a suspension system can be divided into sprung and unsprung mass.Unsprung mass is comprised of the sum of all vehicle parts that movewith a suspended wheel. Sprung mass is comprised of the sum of vehicleparts that can remain stationary as a suspended wheel is moved. Thedynamic center of the sprung mass as shown in FIG. 14 is a combinationof rider and/or passenger mass and the vehicle mass.

The combination of a rider's mass and the sprung mass of the bicycle arealways supported fully by the combination of the vehicle's tires.Powered forward acceleration transfers mass from the vehicle's forwardwheel(s) to the vehicle's driven wheel(s), braking transfers mass fromthe vehicle's forward wheel(s) to the vehicle's driven wheel(s). Ridingon the driven wheel(s) only transfers all of the mass to the drivenwheel(s), and riding on the forward wheel(s) only transfers all of themass to the forward wheel(s).

Due to their combination of short wheelbase (WB) and high center ofgravity (CG), motorcycles and bicycles experience the affects of loadtransfer to a much greater extent than other vehicles in existence. Theratio of the distance from the ground to the CG and the distance betweenthe points where the wheels touch the ground (WB) illustrates thispoint. For example, a common bicycle will exhibit a center of gravity towheelbase ratio of nearly 100%, motorcycles are typically near 50%, andpassenger cars are typically near 25%. Mass transfer is sometimes alsoreferred to as load transfer.

Energy loss through mass transfer is discussed. One undesirable effectof driven wheel suspension systems is the loss of energy in the way ofextreme suspension compression or extension during powered acceleration.This suspension compression or extension is categorized as squat.

A suspension system's geometry and positional relationships between thevehicle drive system components can greatly affect the internaldistribution of forces within the vehicle chassis. As a suspensionsystem cycles through its suspension travel, the positionalrelationships between the suspension system and the vehicle drive systemcan change, and at the same time, the suspension geometry itself willchange. These fluctuations of internal forces are what govern suspensionresponse to powered acceleration and braking. Vehicle attitude inrelation to gravity, and sprung weight center of mass change will alsogovern suspension response to powered acceleration and braking. Theseexternal forces are considered stationary and equal when comparing likevehicles in order to determine squat characteristics.

Squat is the result of internal chassis forces that can cause a rearsuspension to extend or compress during powered acceleration. Squat isan instantaneous condition that can vary throughout the suspensiontravel. Squat has both a direction and magnitude. A squat response canbe measured in relation to itself, and also in relation to outsideconditions. Instantaneous squat response is governed by sprung mass CGplacement, suspension geometry, powertrain component location, and gradein relation to gravity that the vehicle is traveling on. Sprung mass CGplacement only defines the magnitude of squat present in a suspension,and does not change the squat direction conditions. The squat conditionsdefine the direction of squat force in relation to gravity.

There are three squat conditions that must be considered.

The first condition is pro-squat, and describes the condition presentwhen a rear suspension is forced to compress by internal suspensionforces under powered acceleration. Pro-squat is assigned a negativemagnitude value when determining a squat magnitude.

The second condition is anti-squat. Anti-squat describes the conditionpresent when a rear suspension compression is counteracted by internalsuspension forces under powered acceleration. Anti-squat is assigned apositive magnitude value when determining a squat magnitude.

The third condition is zero-squat. Zero-squat occurs only at the instantin between pro-squat and anti-squat, where no suspension manipulatingforces are present under powered acceleration. A vehicle suspensionoperating at the point of zero-squat will not use acceleration forces tomanipulate suspension reaction in any way, or in other words, zero-squathas a squat magnitude value of zero.

Squat force works independent of the spring force that supports asuspended vehicle. Because the squat force is independent of the vehiclespring force, when under acceleration, a vehicle suspension is actedupon by its spring and the squat force together. Suspended vehicles usesprings to support the vehicle chassis and dampers to dissipate impactenergy when the suspension system is compressed and extended while thevehicle travels over rough terrain.

Springs can be in the form of compressive gas springs, leaf springs, orcoil springs, and dampers can use fluid or friction to dissipate energy.There are also rotary damper and spring units in existence. When avehicle is at rest, suspended wheels are compressed a certain amount sothat the suspended wheel can follow irregular road surfaces with bothbumps and dips. The spring that supports a wheel suspension acts as anenergy storage device. Vehicle suspensions use the damper units todissipate energy stored in a spring after the spring is compressed. Thefurther a spring is compressed, the more energy is stored, and the moreenergy will be dissipated by the damper when the spring rebounds.Because spring force increases as a wheel is compressed into itssuspension travel, force at the suspended wheel also increases. Partialcompressive movement of a suspended driven wheel can also be referred toas suspension travel. Complete compressive movement of a suspendeddriven wheel can also be referred to as suspension travel. Driven wheelsuspension travel distance can also be referred to as suspension travel.

Squat magnitude curve graphing is discussed. A squat magnitude curvegraph is a representation of the squat characteristics of a compressiblesuspension under powered acceleration during suspension compressionbeginning at complete suspension extension and ending at completesuspension compression versus percent suspension travel. The squatmagnitude curve graph is laid out so that the percentage of suspensiontravel is graphed on the X axis, and escalating in a positive direction.The minimum suspension travel, which is zero percent suspensioncompression, is shown at the far left of the x-axis, and the maximumsuspension travel, which is 100 percent suspension compression, is shownat the far right of the x-axis. Percent suspension compression may bemeasured and graphed in minimum increments of preferably 5 percent totalsuspension compression. Percent squat magnitude is graphed on the y-axiswith a zero-percent value graphed at the intersection of the x-axis andy-axis, and a 100 percent value graphed above the x-axis. Negativepercent squat values are graphed below the x-axis. The percent squatmagnitude is represented as a percentage of the squat magnitude to thesquat magnitude definition. Percent squat magnitude is calculated bydividing the value of the squat magnitude by the value of the squatmagnitude definition. Squat magnitude value is measured as theperpendicular distance between the lower squat measurement definitionline and the squat definition point. Squat magnitude definition value ismeasured as the perpendicular distance between the lower squatmeasurement definition line and the squat magnitude definition point.Zero percent squat magnitude is always measured at the point of zerosquat condition. This zero squat condition is measured when the squatdefinition point lies directly on the lower squat measurement definitionline. At this point, the squat magnitude measurement has no value. The100 percent squat magnitude value is defined by the location of thesquat magnitude definition point, which is graphed on the squat layoutline. Any magnitude measurement of a squat definition point that liesbelow the lower squat definition line is equal to a pro squat magnitude,and must be graphed as a negative percentage of the positive 100 percentsquat magnitude value. Any magnitude measurement of a squat definitionpoint that lies below the above the squat magnitude definition point hasan anti-squat magnitude, and must be graphed as a higher percentage ofthe positive 100 percent squat magnitude value. Anti-squat is shown atpoints on the squat magnitude curve which are above the x-axis.Zero-squat is shown at points on the squat magnitude curve whichterminate at zero value on the y-axis, coincident with the x-axis, andpro squat is shown at points on the squat magnitude curve which aregraphed below the x-axis. When desired percent squat magnitude valuesare known and graphed versus their corresponding percent measuredsuspension compression values, the points can be connected from point topoint using typical graphing method. A curve can then be fit to thepoint to point graph so that the curve represents a smoothed best fitversion of the point to point graph. The most efficient method to obtainsuch a curve is to use a computer program such as Microsoft Excel,available from Microsoft Corporation, One Microsoft Way, Redmond, Wash.98052-6399, USA. Using Microsoft Excel, a user can input the escalatingsuspension travel measurements beginning with the zero percentmeasurement and ending with the 100 percent measurement, and can inputthe calculated or preferred percent squat magnitude values that coincidewith their percent suspension travel measurements. Microsoft Excel thencan be used to create a graph of the points with a curve fit to thegraphed points. This graphed curve of the percent squat magnitude versusthe percent suspension compression is the discussed squat magnitudecurve.

A stable squat magnitude curve of the invention defines a squatmagnitude curve upper bound, and a squat magnitude curve lower bound.The squat magnitude curve upper bound lies parallel to the x-axis on thesquat magnitude graph. The squat magnitude curve upper bound liescoincident to the highest y value on the squat magnitude curve. Thesquat magnitude curve lower bound lies parallel to the x-axis on thesquat magnitude graph. The squat magnitude curve lower bound liescoincident to the lowest y value on the squat magnitude curve. Bygraphing the squat magnitude curve upper bound and the squat magnitudecurve lower bound in relation to the squat magnitude curve, a percentsquat magnitude variation value can be measured. The percent squatmagnitude variation is a measurement of the amount of deviation in squatmagnitude in the squat magnitude curve. Lower percent squat magnitudevariation amounts will yield a more constant squat magnitude responseover the range of suspension travel, and higher percent squat magnitudevariation amounts will yield a less constant squat magnitude responseover the range of suspension travel.

In certain embodiments, a stable squat magnitude curve of the inventionhas a percent squat magnitude variation value of 0 to 25 percent, orabout 0 to about 25 percent; 0 to 20 percent, or about 0 to about 20percent; of 0 to 18 percent, or about 0 to about 18 percent; of 0 to 18percent, or about 0 to about 16.5 percent; of 0 to 16.5 percent, orabout 0 to about 15 percent; of 0 to 15 percent, or about 0 to about 14percent; of 0 to 14 percent, or about 0 to about 14 percent; of 0 to 13percent, or about 0 to about 13 percent; of 0 to 12 percent, or about 0to about 12 percent; of 0 to 11 percent, or about 0 to about 11 percent;of 0 to 10 percent, or about 0 to about 10 percent; of 0 to 9 percent,or about 0 to about 9 percent; of 0 to 8 percent, or about 0 to about 8percent; of 0 to 7 percent, or about 0 to about 7 percent; of 0 to 6percent, or about 0 to about 6 percent; of 0 to 5 percent, or about 0 toabout 5 percent; of 0 to 4.5 percent, or about 0 to about 4.5 percent;of 0 to 4 percent, or about 0 to about 4 percent; of 0 to 3.5 percent,or about 0 to about 3.75 percent; of 0 to 3.5 percent, or about 0 toabout 3.5 percent; of 0 to 3.25 percent, or about 0 to about 3.25percent; of 0 to 3 percent, or about 0 to about 3 percent; of 0 to 2.75percent, or about 0 to about 2.75 percent; of 0 to 2.5 percent, or about0 to about 2.5 percent; of 0 to 2.25 percent, or about 0 to about 2.25percent; of 0 to 2 percent, or about 0 to about 2 percent; of 0 to 1.75percent, or about 0 to about 1.75 percent; of 0 to 1.5 percent, or about0 to about 1.5 percent; of 0 to 1.25 percent, or about 0 to about 1.25percent; of 0 to 1 percent, or about 0 to about 1 percent; of 0 to 0.75percent, or about 0 to about 0.75 percent; of 0 to 0.5 percent, or about0 to about 0.5 percent; of 0 to 0.25 percent, or about 0 to about 0.25percent; of 0 to 0.15 percent, or about 0 to about 0.15 percent; of 0 to0.10 percent, or about 0 to about 0.10 percent; of 0 to 0.10 percent, orabout 0 to about 0.10 percent; of 0 to 0.05 percent, or about 0 to about0.05 percent; of 0 to 0.025 percent, or about 0 to about 0.025 percent;of 0 to 0.010 percent, or about 0 to about 0.010 percent; of 0 to 0.005percent, or about 0 to about 0.005 percent; of 0 to 0.001 percent, orabout 0 to about 0.001 percent.

Slope of a squat magnitude curve between two points on a curve isdefined by the standard coordinate geometry equation: slope=rise/run. Asquat magnitude curve that has a squat magnitude at zero suspensiontravel, with 20 percent less squat magnitude at a point 10 percent intothe wheel suspension travel compression, will have a slope of −2,because per the equation slope=rise/run, −0.2/0.1=−2. A squat magnitudecurve that has a pro squat magnitude at zero suspension travel, with 20percent greater pro squat magnitude at a point 10 percent into the wheelsuspension travel compression will have a slope of −2, because per theequation slope=rise/run, −0.2/0.1=−2. A squat magnitude curve can beproduced for any wheel suspension system by graphing the percent ofsquat magnitude at points throughout the suspension travel versus thecorresponding suspension travel points in the suspension travel. It willbe understood that as common graphical method dictated, a more accurateslope measurement of a path can be determined when the two points on apath defining a slope line are as close together as possible.

In certain embodiments, a suspension system according to the inventionhas a squat magnitude curve with a varying slope. In certain preferredembodiments, the slope of the squat magnitude curve is negative at thebeginning of suspension travel and positive at a further point in thesuspension travel. In certain other preferred embodiments, the slope ofthe squat magnitude curve is positive at the beginning of suspensiontravel and negative at a further point in the suspension travel. Incertain other preferred embodiments, the slope of the squat magnitudecurve is positive at the beginning of suspension travel, then negativeat a further point in the suspension travel, then positive at a stillfurther point in the suspension travel. In certain other preferredembodiments, the slope of the squat magnitude curve can vary betweenpositive and negative multiple times as a driven wheel is moved throughits suspension travel distance.

Percentage of suspension travel escalates in a positive amount as adriven wheel suspension is compressed. In certain embodiments, thebeginning of the suspension travel is 0 to 50 percent, or about 0 toabout 50 percent, of suspension travel; or 0 to 40 percent, or about 0to about 40 percent, of suspension travel; or 0 to 30 percent, or about0 to about 30 percent, of suspension travel; or 0 to 20 percent, orabout 0 to about 20 percent, of suspension travel; or 0 to 10 percent,or about 0 to about 10 percent, of suspension travel; or 0 to 5 percent,or about 0 to about 5 percent, of suspension travel; or 0 or about 0percent of suspension travel. In certain embodiments, the interim, ormid range, of the suspension travel is 25 to 75 percent, or about 25 toabout 75 percent, of suspension travel; or 30 to 70 percent, or about 30to about 70 percent, of suspension travel; or 35 to 65 percent, or about35 to about 65 percent, of suspension travel; or 40 to 60 percent, orabout 40 to about 60 percent, of suspension travel; or 45 to 55 percent,or about 45 to about 55 percent, of suspension travel; or 50 percent orabout 50 percent, of suspension travel; or 60 to 80 percent, or about 60to about 80 percent, of suspension travel; or 65 to 75 percent, or about65 to about 75 percent, of suspension travel; or 70 percent or about 70of suspension travel; or 50 to 60 percent, or about 50 to about 60percent, of suspension travel. In certain embodiments, the end of thesuspension travel is 60 to 100 percent, or about 60 to about 100percent, of suspension travel; or 70 to 100 percent, or about 70 toabout 100 percent, of suspension travel; or 75 to 100 percent, or about75 to about 100 percent, of suspension travel; or 80 to 100 percent, orabout 80 to about 100 percent, of suspension travel; or 85 to 100percent, or about 85 to about 100 percent, of suspension travel; or 90to 100 percent, or about 90 to about 100 percent, of suspension travel;or 95 to 100 percent, or about 95 to about 100 percent, of suspensiontravel; or 100 or about 100 percent of suspension travel.

In certain embodiments, a suspension system of the invention has a squatmagnitude curve with a slope in the beginning of suspension travel of−0.0001 to −0.25, or about −0.0001 to about −0.25; of −0.0001 to −0.5,or about −0.0001 to about −0.5; of −0.0001 to −1, or about −0.0001 toabout −1; of −0.0001 to −1.5, or about −0.0001 to about −1.5; of −0.0001to −2, or about −0.0001 to about −2; of −0.0001 to −5, or about −0.0001to about −5; of −0.0001 to −10, or about −0.0001 to about −10; of−0.0001 to −100, or about −0.001 to about −100; of −0.0001 to −1000, orabout −0.001 to about −1000; of −0.0001 to −10000, or about −0.001 toabout −10000; of −0.0001 to −100000, or about −0.001 to about −100000;of −0.2 to −5, or about −0.2 to about −5; of −0.5 to −4.5, or about −0.5to about −4.5; of −0.75 to −4.0, or about −0.75 to about −4.0; of −1.0to −3.5, or about −1.0 to about −3.5; of −1.5 to −3.0, or about −1.5 toabout −3.0; of −2.0 to −2.5, or about −2.0 to about −2.5; of −3.0 to−3.5, or about −3.0 to about −3.5; of −3.5 to −4.0, or about −3.5 toabout −4.0; of −3.5 to −4.5, or about −3.5 to about −4.5; of −4.5 to−5.5, or about −4.5 to about −5.5; of −5.0 to −6.5, or about −5.0 toabout −6.5; of −6.0 to −7.5, or about −6.0 to about −7.5; of −7.0 to−8.5, or about −7.0 to about −8.5; of −8.0 to −9.5, or about −8.0 toabout −9.5; of −9.0 to −12.5, or about −9.0 to about −12.5; of −10.0 to−15.5, or about −10.0 to about −15.5. In certain embodiments, asuspension system of the invention has a squat magnitude curve with aslope in the end of suspension travel of 0.0001 to 0.25, or about 0.0001to about 0.25; of 0.0001 to 0.5, or about 0.0001 to about 0.5; of 0.0001to 1, or about 0.0001 to about 1; of 0.0001 to 1.5, or about 0.0001 toabout 1.5; of 0.0001 to 2, or about 0.0001 to about 2; of 0.0001 to 5,or about 0.0001 to about 5; of 0.0001 to 10, or about 0.0001 to about10; of 0.0001 to 100, or about 0.001 to about 100; of 0.0001 to 1000, orabout 0.001 to about 1000; of 0.0001 to 10000, or about 0.001 to about10000; of 0.0001 to 100000, or about 0.001 to about 100000; of 0.2 to 5,or about 0.2 to about 5; of 0.5 to 4.5, or about 0.5 to about 4.5; of0.75 to 4.0, or about 0.75 to about 4.0; of 1.0 to 3.5, or about 1.0 toabout 3.5; of 1.5 to 3.0, or about 1.5 to about 3.0; of 2.0 to 2.5, orabout 2.0 to about 2.5; of 3.0 to 3.5, or about 3.0 to about 3.5; of 3.5to 4.0, or about 3.5 to about 4.0; of 3.5 to 4.5, or about 3.5 to about4.5; of 4.5 to 5.5, or about 4.5 to about 5.5; of 5.0 to 6.5, or about5.0 to about 6.5; of 6.0 to 7.5, or about 6.0 to about 7.5; of 7.0 to8.5, or about 7.0 to about 8.5; of 8.0 to 9.5, or about 8.0 to about9.5; of 9.0 to 12.5, or about 9.0 to about 12.5; of 10.0 to 15.5, orabout 10.0 to about 15.5.

In certain embodiments, a suspension system of the invention has a squatmagnitude curve with a slope in the beginning of suspension travel of0.0001 to 0.25, or about 0.0001 to about 0.25; of 0.0001 to 0.5, orabout 0.0001 to about 0.5; of 0.0001 to 1, or about 0.0001 to about 1;of 0.0001 to 1.5, or about 0.0001 to about 1.5; of 0.0001 to 2, or about0.0001 to about 2; of 0.0001 to 5, or about 0.0001 to about 5; of 0.0001to 10, or about 0.0001 to about 10; of 0.0001 to 100, or about 0.001 toabout 100; of 0.0001 to 1000, or about 0.001 to about 1000; of 0.0001 to10000, or about 0.001 to about 10000; of 0.0001 to 100000, or about0.001 to about 100000; of 0.2 to 5, or about 0.2 to about 5; of 0.5 to4.5, or about 0.5 to about 4.5; of 0.75 to 4.0, or about 0.75 to about4.0; of 1.0 to 3.5, or about 1.0 to about 3.5; of 1.5 to 3.0, or about1.5 to about 3.0; of 2.0 to 2.5, or about 2.0 to about 2.5; of 3.0 to3.5, or about 3.0 to about 3.5; of 3.5 to 4.0, or about 3.5 to about4.0; of 3.5 to 4.5, or about 3.5 to about 4.5; of 4.5 to 5.5, or about4.5 to about 5.5; of 5.0 to 6.5, or about 5.0 to about 6.5; of 6.0 to7.5, or about 6.0 to about 7.5; of 7.0 to 8.5, or about 7.0 to about8.5; of 8.0 to 9.5, or about 8.0 to about 9.5; of 9.0 to 12.5, or about9.0 to about 12.5; of 10.0 to 15.5, or about 10.0 to about 15.5. Incertain embodiments, a suspension system of the invention has a squatmagnitude curve with a slope in the end of suspension travel of −0.0001to −0.25, or about −0.0001 to about −0.25; of −0.0001 to −0.5, or about−0.0001 to about −0.5; of −0.0001 to −1, or about −0.0001 to about −1;of −0.0001 to −1.5, or about −0.0001 to about −1.5; of −0.0001 to −2, orabout −0.0001 to about −2; of −0.0001 to −5, or about −0.0001 to about−5; of −0.0001 to −10, or about −0.0001 to about −10; of −0.0001 to−100, or about −0.001 to about −100; of −0.0001 to −1000, or about−0.001 to about −1000; of −0.0001 to −10000, or about −0.001 to about−10000; of −0.0001 to −100000, or about −0.001 to about −100000; of −0.2to −5, or about −0.2 to about −5; of −0.5 to −4.5, or about −0.5 toabout −4.5; of −0.75 to −4.0, or about −0.75 to about −4.0; of −1.0 to−3.5, or about −1.0 to about −3.5; of −1.5 to −3.0, or about −1.5 toabout −3.0; of −2.0 to −2.5, or about −2.0 to about −2.5; of −3.0 to−3.5, or about −3.0 to about −3.5; of −3.5 to −4.0, or about −3.5 toabout −4.0; of −3.5 to −4.5, or about −3.5 to about −4.5; of −4.5 to−5.5, or about −4.5 to about −5.5; of −5.0 to −6.5, or about −5.0 toabout −6.5; of −6.0 to −7.5, or about −6.0 to about −7.5; of −7.0 to−8.5, or about −7.0 to about −8.5; of −8.0 to −9.5, or about −8.0 toabout −9.5; of −9.0 to −12.5, or about −9.0 to about −12.5; of −10.0 to−15.5, or about −10.0 to about −15.5. In certain embodiments, asuspension system of the invention has a squat magnitude curve with aslope in the beginning of suspension travel of −0.0001 to −0.25, orabout −0.0001 to about −0.25; of −0.0001 to −0.5, or about −0.0001 toabout −0.5; of −0.0001 to −1, or about −0.0001 to about −1; of −0.0001to −1.5, or about −0.0001 to about −1.5; of −0.0001 to −2, or about−0.0001 to about −2; of −0.0001 to −5, or about −0.0001 to about −5; of−0.0001 to −10, or about −0.0001 to about −10; of −0.0001 to −100, orabout −0.001 to about −100; of −0.0001 to −1000, or about −0.001 toabout −1000; of −0.0001 to −10000, or about −0.001 to about −10000; of−0.0001 to −100000, or about −0.001 to about −100000; of −0.2 to −5, orabout −0.2 to about −5; of −0.5 to −4.5, or about −0.5 to about −4.5; of−0.75 to −4.0, or about −0.75 to about −4.0; of −1.0 to −3.5, or about−1.0 to about −3.5; of −1.5 to −3.0, or about −1.5 to about −3.0; of−2.0 to −2.5, or about −2.0 to about −2.5; of −3.0 to −3.5, or about−3.0 to about −3.5; of −3.5 to −4.0, or about −3.5 to about −4.0; of−3.5 to −4.5, or about −3.5 to about −4.5; of −4.5 to −5.5, or about−4.5 to about −5.5; of −5.0 to −6.5, or about −5.0 to about −6.5; of−6.0 to −7.5, or about −6.0 to about −7.5; of −7.0 to −8.5, or about−7.0 to about −8.5; of −8.0 to −9.5, or about −8.0 to about −9.5; of−9.0 to −12.5, or about −9.0 to about −12.5; of −10.0 to −15.5, or about−10.0 to about −15.5. In certain embodiments, a suspension system of theinvention has a squat magnitude curve with a slope at a further point inthe suspension travel of 0.0001 to 0.25, or about 0.0001 to about 0.25;of 0.0001 to 0.5, or about 0.0001 to about 0.5; of 0.0001 to 1, or about0.0001 to about 1; of 0.0001 to 1.5, or about 0.0001 to about 1.5; of0.0001 to 2, or about 0.0001 to about 2; of 0.0001 to 5, or about 0.0001to about 5; of 0.0001 to 10, or about 0.0001 to about 10; of 0.0001 to100, or about 0.001 to about 100; of 0.0001 to 1000, or about 0.001 toabout 1000; of 0.0001 to 10000, or about 0.001 to about 10000; of 0.0001to 100000, or about 0.001 to about 100000; of 0.2 to 5, or about 0.2 toabout 5; of 0.5 to 4.5, or about 0.5 to about 4.5; of 0.75 to 4.0, orabout 0.75 to about 4.0; of 1.0 to 3.5, or about 1.0 to about 3.5; of1.5 to 3.0, or about 1.5 to about 3.0; of 2.0 to 2.5, or about 2.0 toabout 2.5; of 3.0 to 3.5, or about 3.0 to about 3.5; of 3.5 to 4.0, orabout 3.5 to about 4.0; of 3.5 to 4.5, or about 3.5 to about 4.5; of 4.5to 5.5, or about 4.5 to about 5.5; of 5.0 to 6.5, or about 5.0 to about6.5; of 6.0 to 7.5, or about 6.0 to about 7.5; of 7.0 to 8.5, or about7.0 to about 8.5; of 8.0 to 9.5, or about 8.0 to about 9.5; of 9.0 to12.5, or about 9.0 to about 12.5; of 10.0 to 15.5, or about 10.0 toabout 15.5.

In certain embodiments, a suspension system of the invention has a squatmagnitude curve with a slope in the beginning of suspension travel of0.0001 to 0.25, or about 0.0001 to about 0.25; of 0.0001 to 0.5, orabout 0.0001 to about 0.5; of 0.0001 to 1, or about 0.0001 to about 1;of 0.0001 to 1.5, or about 0.0001 to about 1.5; of 0.0001 to 2, or about0.0001 to about 2; of 0.0001 to 5, or about 0.0001 to about 5; of 0.0001to 10, or about 0.0001 to about 10; of 0.0001 to 100, or about 0.001 toabout 100; of 0.0001 to 1000, or about 0.001 to about 1000; of 0.0001 to10000, or about 0.001 to about 10000; of 0.0001 to 100000, or about0.001 to about 100000; of 0.2 to 5, or about 0.2 to about 5; of 0.5 to4.5, or about 0.5 to about 4.5; of 0.75 to 4.0, or about 0.75 to about4.0; of 1.0 to 3.5, or about 1.0 to about 3.5; of 1.5 to 3.0, or about1.5 to about 3.0; of 2.0 to 2.5, or about 2.0 to about 2.5; of 3.0 to3.5, or about 3.0 to about 3.5; of 3.5 to 4.0, or about 3.5 to about4.0; of 3.5 to 4.5, or about 3.5 to about 4.5; of 4.5 to 5.5, or about4.5 to about 5.5; of 5.0 to 6.5, or about 5.0 to about 6.5; of 6.0 to7.5, or about 6.0 to about 7.5; of 7.0 to 8.5, or about 7.0 to about8.5; of 8.0 to 9.5, or about 8.0 to about 9.5; of 9.0 to 12.5, or about9.0 to about 12.5; of 10.0 to 15.5, or about 10.0 to about 15.5. Incertain embodiments, a suspension system of the invention has a squatmagnitude curve with a slope at a further point in the suspension travelof −0.0001 to −0.25, or about −0.0001 to about −0.25; of −0.0001 to−0.5, or about −0.0001 to about −0.5; of −0.0001 to −1, or about −0.0001to about −1; of −0.0001 to −1.5, or about −0.0001 to about −1.5; of−0.0001 to −2, or about −0.0001 to about −2; of −0.0001 to −5, or about−0.0001 to about −5; of −0.0001 to −10, or about −0.0001 to about −10;of −0.0001 to −100, or about −0.001 to about −100; of −0.0001 to −1000,or about −0.001 to about −1000; of −0.0001 to −10000, or about −0.001 toabout −10000; of −0.0001 to −100000, or about −0.001 to about −100000;of −0.2 to −5, or about −0.2 to about −5; of −0.5 to −4.5, or about −0.5to about −4.5; of −0.75 to −4.0, or about −0.75 to about −4.0; of −1.0to −3.5, or about −1.0 to about −3.5; of −1.5 to −3.0, or about −1.5 toabout −3.0; of −2.0 to −2.5, or about −2.0 to about −2.5; of −3.0 to−3.5, or about −3.0 to about −3.5; of −3.5 to −4.0, or about −3.5 toabout −4.0; of −3.5 to −4.5, or about −3.5 to about −4.5; of −4.5 to−5.5, or about −4.5 to about −5.5; of −5.0 to −6.5, or about −5.0 toabout −6.5; of −6.0 to −7.5, or about −6.0 to about −7.5; of −7.0 to−8.5, or about −7.0 to about −8.5; of −8.0 to −9.5, or about −8.0 toabout −9.5; of −9.0 to −12.5, or about −9.0 to about −12.5; of −10.0 to−15.5, or about −10.0 to about −15.5.

In certain embodiments, a suspension system of the invention has a squatmagnitude curve with a slope in the beginning of suspension travel of0.0001 to 0.25, or about 0.0001 to about 0.25; of 0.0001 to 0.5, orabout 0.0001 to about 0.5; of 0.0001 to 1, or about 0.0001 to about 1;of 0.0001 to 1.5, or about 0.0001 to about 1.5; of 0.0001 to 2, or about0.0001 to about 2; of 0.0001 to 5, or about 0.0001 to about 5; of 0.0001to 10, or about 0.0001 to about 10; of 0.0001 to 100, or about 0.001 toabout 100; of 0.0001 to 1000, or about 0.001 to about 1000; of 0.0001 to10000, or about 0.001 to about 10000; of 0.0001 to 100000, or about0.001 to about 100000; of 0.2 to 5, or about 0.2 to about 5; of 0.5 to4.5, or about 0.5 to about 4.5; of 0.75 to 4.0, or about 0.75 to about4.0; of 1.0 to 3.5, or about 1.0 to about 3.5; of 1.5 to 3.0, or about1.5 to about 3.0; of 2.0 to 2.5, or about 2.0 to about 2.5; of 3.0 to3.5, or about 3.0 to about 3.5; of 3.5 to 4.0, or about 3.5 to about4.0; of 3.5 to 4.5, or about 3.5 to about 4.5; of 4.5 to 5.5, or about4.5 to about 5.5; of 5.0 to 6.5, or about 5.0 to about 6.5; of 6.0 to7.5, or about 6.0 to about 7.5; of 7.0 to 8.5, or about 7.0 to about8.5; of 8.0 to 9.5, or about 8.0 to about 9.5; of 9.0 to 12.5, or about9.0 to about 12.5; of 10.0 to 15.5, or about 10.0 to about 15.5. Incertain embodiments, a suspension system of the invention has a squatmagnitude curve with a slope at a further point in the suspension travelof −0.0001 to −0.25, or about −0.0001 to about −0.25; of −0.0001 to−0.5, or about −0.0001 to about −0.5; of −0.0001 to −1, or about −0.0001to about −1; of −0.0001 to −1.5, or about −0.0001 to about −1.5; of−0.0001 to −2, or about −0.0001 to about −2; of −0.0001 to −5, or about−0.0001 to about −5; of −0.0001 to −10, or about −0.0001 to about −10;of −0.0001 to −100, or about −0.001 to about −100; of −0.0001 to −1000,or about −0.001 to about −1000; of −0.0001 to −10000, or about −0.001 toabout −10000; of −0.0001 to −100000, or about −0.001 to about −100000;of −0.2 to −5, or about −0.2 to about −5; of −0.5 to −4.5, or about −0.5to about −4.5; of −0.75 to −4.0, or about −0.75 to about −4.0; of −1.0to −3.5, or about −1.0 to about −3.5; of −1.5 to −3.0, or about −1.5 toabout −3.0; of −2.0 to −2.5, or about −2.0 to about −2.5; of −3.0 to−3.5, or about −3.0 to about −3.5; of −3.5 to −4.0, or about −3.5 toabout −4.0; of −3.5 to −4.5, or about −3.5 to about −4.5; of −4.5 to−5.5, or about −4.5 to about −5.5; of −5.0 to −6.5, or about −5.0 toabout −6.5; of −6.0 to −7.5, or about −6.0 to about −7.5; of −7.0 to−8.5, or about −7.0 to about −8.5; of −8.0 to −9.5, or about −8.0 toabout −9.5; of −9.0 to −12.5, or about −9.0 to about −12.5; of −10.0 to−15.5, or about −10.0 to about −15.5. In certain embodiments, asuspension system of the invention has a squat magnitude curve with aslope at a still further point in the suspension travel of 0.0001 to0.25, or about 0.0001 to about 0.25; of 0.0001 to 0.5, or about 0.0001to about 0.5; of 0.0001 to 1, or about 0.0001 to about 1; of 0.0001 to1.5, or about 0.0001 to about 1.5; of 0.0001 to 2, or about 0.0001 toabout 2; of 0.0001 to 5, or about 0.0001 to about 5; of 0.0001 to 10, orabout 0.0001 to about 10; of 0.0001 to 100, or about 0.001 to about 100;of 0.0001 to 1000, or about 0.001 to about 1000; of 0.0001 to 10000, orabout 0.001 to about 10000; of 0.0001 to 100000, or about 0.001 to about100000; of 0.2 to 5, or about 0.2 to about 5; of 0.5 to 4.5, or about0.5 to about 4.5; of 0.75 to 4.0, or about 0.75 to about 4.0; of 1.0 to3.5, or about 1.0 to about 3.5; of 1.5 to 3.0, or about 1.5 to about3.0; of 2.0 to 2.5, or about 2.0 to about 2.5; of 3.0 to 3.5, or about3.0 to about 3.5; of 3.5 to 4.0, or about 3.5 to about 4.0; of 3.5 to4.5, or about 3.5 to about 4.5; of 4.5 to 5.5, or about 4.5 to about5.5; of 5.0 to 6.5, or about 5.0 to about 6.5; of 6.0 to 7.5, or about6.0 to about 7.5; of 7.0 to 8.5, or about 7.0 to about 8.5; of 8.0 to9.5, or about 8.0 to about 9.5; of 9.0 to 12.5, or about 9.0 to about12.5; of 10.0 to 15.5, or about 10.0 to about 15.5.

Graphical kinematical squat magnitude curves are discussed. Graphicalmethods can be used to determine suspension kinematical layout used toattain a desired squat magnitude curve for a suspension. For shaftdriven, chain driven, and spindle driven vehicles, graphical layout isidentical until factoring in the unique features of each powertrain. Anysuspended wheel in a vehicle has an axle path that a wheel follows whena suspension is moved through suspension travel. The curvature of thisaxle path and its layout in relation to specific powertrain componentsdefine a squat magnitude curve. A squat magnitude curve is a measurementof the changing magnitude and direction of squat in relation to externalelements, such as vehicle attitude in relation to gravity, that definetotal squat magnitude. For analysis purposes, it is understood thatthese external elements are well defined, and during analysis remainconstant to attain results that can be used to directly compare varioussystems. With external elements defined and unchanging, squat isdeveloped under powered acceleration, and through changes in internalgeometry of the vehicle center of mass location, vehicle suspension, andpowertrain, as a suspension system is cycled through suspension travelfrom its beginning uncompressed point to its ending fully compressedpoint. Every instantaneous point in a suspension travel has acorresponding instantaneous squat point with a squat magnitude valuepresent. These instantaneous squat points can be measured or graphed asa point on the squat layout line at a perpendicular distance from thelower squat layout line. Squat magnitude value is measured as theperpendicular distance between the lower squat measurement definitionline and the squat definition point. Squat magnitude definition value ismeasured as the perpendicular distance between the lower squatmeasurement definition line and the squat magnitude definition point.When the desired instantaneous amounts of squat at instantaneous pointsin the suspension travel are known, squat definition points can begraphed kinematically in conjunction with each other, beginning when asuspension is in its uncompressed state and ending in its fullycompressed state, and in relation to the vehicle geometry to obtain asuspension kinematical layout which will attain the desired squatmagnitude curve. The squat magnitude curve beginning value is defined bythe squat magnitude measured where the suspension system is in itscompletely uncompressed state. As the suspension is cycled furtherthrough suspension travel towards complete compression pausing at aminimum of 5 percent total suspension travel increments, further squatdefinition values are measured and recorded. At the same intervals, thesquat magnitude definition values are recorded. The squat magnitudevalues are divided by the squat magnitude definition values to attainthe percent squat values. The percent squat values are graphed versustheir correlating escalating percent total suspension travel increments.Suspension travel displacement is measured in a direction parallel toand against gravity and parallel to the instantaneous squat pointmeasurements when the vehicle is on level ground with the suspensionfully extended. This measurement direction is always measured first withthe vehicle on level ground with the suspension fully extended, andremains constant to the vehicle chassis when measuring suspension travelunder circumstances where the vehicle is not placed on level ground orwhen suspension is compressed. Critical and known preexisting definingpoints such as vehicle wheelbase, powertrain location, and center ofmass are graphed alongside the squat definition points to obtain a clearpicture of vehicle squat performance. Vehicle graphs for obtaining anddefining squat performance are always laid out with the vehicle viewedin the side elevational view.

A squat layout line is drawn parallel to and against gravitational forcethrough center of the forward wheel contact patch between the tire andthe ground and terminating at further points. A squat definition point,which can be calculated directly from the aforementioned squat magnitudecurve or graphed kinematically as described previously will be graphedon this squat layout line. A squat lower measurement definition line isdrawn from the center of the driven wheel tire to ground contact patchperpendicular to and terminating on the squat layout line. Squatdefinition points are drawn on the squat definition line in relation toone another, and in relation to the squat lower measurement definitionline. A squat definition point drawn above the squat lower measurementdefinition line will correlate with an anti squat magnitude. A squatdefinition point drawn coincident with the squat lower measurementdefinition line will correlate with a zero squat magnitude. A squatdefinition point drawn below the squat lower measurement definition linewill correlate with a pro squat magnitude. A squat force vector is drawnfrom the center of the driven wheel tire to ground contact patch to thesquat definition point on the squat layout line. As the suspension ismoved through instantaneous measured points through suspension travel,the squat force vector is drawn with a beginning point at the center ofthe rear tire to ground contact patch, and an ending point at itscorresponding measured instantaneous squat definition point graphed onthe squat layout line. A squat magnitude definition point will begraphed on this squat layout line. A squat lower measurement definitionline is drawn from the center of the driven wheel tire to ground contactpatch perpendicular to and terminating on the squat layout line. Theknown vehicle center of sprung mass is graphed in relation to thevehicle. A center of mass intersection vector is drawn from the centerof the driven wheel tire to ground contact patch, through the center ofmass, and terminating on the squat layout line. The point at which thecenter of mass intersection vector meets the squat layout line isdefined as the 200 percent squat point. The distance between the squat200 percent squat point and the squat lower measurement definition lineis referred to as the 200 percent measurement value. A point halfwaybetween the 200 percent squat point and the squat lower measurementdefinition line is defined as the squat magnitude definition point. Bydividing the 200 percent measurement value by two, the squat magnitudedefinition value can be obtained. The distance between the squatmagnitude definition point and the squat lower measurement definitionline is referred to as the squat measurement definition value.

Diversion in graphical method to obtain specific suspension systemkinematical layouts from a desired squat magnitude curve must occur whenfactoring in specifics for different types of power transfer systemssuch as shaft drive, spindle drive, or chain drive.

A shaft drive system generally uses a power transmission system that cantransmit power via rotary motion from a power unit output shaft to awheel shaft. The two shafts are generally fixed at close to aperpendicular angle in one plane. Power transmission systems can varyfrom gears to cogs to friction wheels and other types of systems, allherein referred to universally as cogs. These shaft drive systemsfeature a driving cog which is rotatably attached to the power unitoutput, a first intermediate cog, which transfers rotational motion fromthe driving cog to a relatively perpendicular shaft, a secondintermediate cog, which transfers rotational motion from the shaft to adriven cog which is rotatably attached to the rotation axis of a wheel.

Shaft drive vehicle powertrains and suspensions typically take one oftwo forms. These are, a single pivot system, or a multi link system. Asimple single pivot system features a driven cog that is fixed to andhoused within a wheel carrier link which pivots around a single pivot.In this arrangement, there is only one pivot connecting the wheelcarrier link to the vehicle frame structure. The rotating drive torqueis acted against by the driven cog housing, which is part of the wheelcarrier link. Action against the drive torque in the wheel carrier linkcauses a torque about the single frame pivot. The addition of thistorque plus the driving force imparted through the wheel tirecombination to the ground through a tire to ground contact patch totalsa squat response. An instantaneous pivot location for a single pivotshaft drive system can be found at any point on a drawn squat forcevector that correlates with the desired instantaneous squat response.These single pivot systems are incapable of producing a stable squatmagnitude curve.

A multi pivot linkage can be used to alter squat characteristics andobtain a variable squat magnitude curve in a shaft driven wheelsuspension system. A multi link shaft drive suspension system isolatesthe torque passed through the driven cog in the system from the swinginglink system. In a 4-bar variation, the driven cog is attached to a wheelcarrier link, which pivots at one end of a first swinging link. Thefirst carrier manipulation link is pivotally attached to the vehiclechassis at the end opposite of the wheel carrier link pivot. A torquereaction, like the one discussed in the single pivot shaft drive systemworks to rotate the wheel carrier link against the first carriermanipulation link. A second carrier manipulation link is also attachedto the wheel carrier link. This second carrier manipulation link isattached to the vehicle chassis at a different location from the firstswinging carrier manipulation link. The second carrier manipulation linkworks to inhibit free rotation of the wheel carrier link against thefirst carrier manipulation link. To find instantaneous carriermanipulation link pivot points which will give a desired instantaneoussquat magnitude, its correlating desired squat force vector must begraphed. The two wheel carrier link pivots are next defined. Carriermanipulation link force lines are drawn so that a force line passesdirectly through the center of the rearward pivots which are coincidentwith the pivots on the wheel carrier link. The carrier manipulation linkforce lines are drawn so that they intersect on the desired squat forcevector. The first and second vehicle chassis pivots can be positionedupon the corresponding first and second carrier manipulation link forcelines to attain the desired instantaneous squat response. Graphing thecarrier manipulation link force lines and desired squat force vectorstogether overlaid at multiple points in the suspension travel will allowthe designer to choose pivot point locations and kinematical suspensionlayout that can attain a desired variable squat magnitude curve.

A spindle driven system generally uses a power transmission system thatcan transmit power via rotary motion from a power unit output shaft to awheel shaft spindle. This type of system is useful for multi wheeledvehicles using independently suspended or partially independentlysuspended driven wheels. The power unit output shaft and wheel shaftspindle are generally fixed at close to a parallel angle in one plane.The power unit output shaft is fixed to the suspended frame member andis rotatably coupled to the wheel shaft spindle so that both the using aconstant velocity or universal type joint and wheel shaft spindle rotatein the same direction. Power transmission between the power unit outputshaft and wheel shaft spindle for spindle driven suspension systemscould incorporate an intermediate shaft that is connected to the powerunit output shaft using a constant velocity or universal type joint andto the wheel shaft spindle using a constant velocity or universal typejoint. The intermediate shaft and associated constant velocity oruniversal type joints transfer rotational motion to the wheel shaftspindle which is attached to the driven wheel so that the driven wheelrotates about the driven wheel rotation axis.

Spindle driven vehicle independent and semi independent suspensionstypically take one of several forms. These are; a single pivot trailingarm system, a single pivot semi trailing arm system, swing axle system,an A-Arm or H-Arm system, a MacPherson strut system, or a long arm 4-barsemi-parallel link system.

A simple single pivot trailing arm or single pivot semi trailing armsystem features a wheel shaft spindle that is rotatably attached to awheel carrier link which pivots around a single pivot. In thisarrangement, there is only one pivot connecting the wheel carrier linkto the vehicle frame structure. The wheel carrier link is arranged sothat the frame pivot axis project towards the right and left side of thevehicle. In the single pivot trailing arm system, this frame pivot iswide enough to support side loads under vehicle cornering, and the axisabout which the wheel carrier link pivots is parallel with the wheelshaft spindle. In the single pivot semi trailing arm system, this framepivot is wide enough to support side loads under vehicle cornering, andthe axis about which the wheel carrier link pivots is parallel with thewheel shaft spindle. The wheel carrier link is arranged so that theframe pivot axis project diagonally towards the right and left side andfront and back of the vehicle. As the driven wheel is accelerated, thedriving force imparted through the wheel tire combination to the groundthrough a tire to ground contact patch is transferred through the drivenwheel structure, into the wheel shaft spindle. This driving force istransmitted to the wheel carrier link through the rotatable connectionbetween the wheel shaft spindle, and wheel carrier link. The drivingforce, acting through the wheel carrier link on the single frame pivottotals a squat response. An instantaneous pivot location for a singlepivot spindle drive system can be found at any point on a drawn squatforce vector that correlates with the desired instantaneous squatresponse. These single pivot systems are incapable of producing a stablesquat magnitude curve.

A swing axle system features a wheel shaft spindle that is rotatablyattached to a wheel carrier link which pivots around a single pivot. Inthis arrangement, there is only one pivot connecting the wheel carrierlink to the vehicle frame structure. The wheel carrier link is arrangedso that the frame pivot axis project towards the front and back of thevehicle. In the swing axle system, this frame pivot is wide enough tosupport side loads under vehicle cornering, and the axis about which thewheel carrier link pivots is perpendicular to the wheel shaft spindle.As the driven wheel is accelerated, the driving force imparted throughthe wheel tire combination to the ground through a tire to groundcontact patch is transferred through the driven wheel structure, intothe wheel shaft spindle. This driving force is transmitted to the wheelcarrier link through the rotatable connection between the wheel shaftspindle, and wheel carrier link. The driving force, acting through thewheel carrier link on the single frame pivot totals a squat response. Aninstantaneous pivot location for a single pivot spindle drive system canbe found at any point on a drawn squat force vector that correlates withthe desired instantaneous squat response. These single pivot systems areincapable of producing a stable squat magnitude curve.

An A-Arm or H-Arm system features a wheel shaft spindle that isrotatably attached to a wheel carrier link which is pivotally attachedto a frame structure through upper and lower carrier manipulation links.The wheel carrier link and upper and lower carrier manipulation linksare arranged so that the link pivot axis project towards the front andback of the vehicle, perpendicular to the wheel shaft spindle. In theA-Arm or H-Arm system, these frame pivots are spaced to support sideloads under vehicle cornering. The A-Arm and H-Arm systems dynamicallycan accomplish nearly identical results, with the variation being thatan A-Arm system uses an additional support arm to control wheel turningfor steering purposes, and an H-Arm uses an additional pivot on one armto control wheel turning for steering purposes. As the driven wheel isaccelerated, the driving force imparted through the wheel tirecombination to the ground through a tire to ground contact patch istransferred through the driven wheel structure, into the wheel shaftspindle. This driving force is transmitted to the wheel carrier linkthrough the rotatable connection between the wheel shaft spindle, andwheel carrier link. The driving force, acting through the wheel carrierlink on the upper and lower carrier manipulation links and frame pivotstotals a squat response. These A-Arm and H-Arm systems are incapable ofproducing a stable squat magnitude curve.

A MacPherson Strut system features a wheel shaft spindle that isrotatably attached to a wheel carrier link which is attached to a framestructure through a carrier manipulation link and an axial slidingshaft. The carrier manipulation link and axial sliding shaft arearranged so that the link pivot axis project towards the front and backof the vehicle, perpendicular to the wheel shaft spindle. In theMacPherson Strut system, these frame pivots are spaced to support sideloads under vehicle cornering. The MacPherson system uses an additionalsupport arm to control the wheel turning for steering purposes. As thedriven wheel is accelerated, the driving force imparted through thewheel tire combination to the ground through a tire to ground contactpatch is transferred through the driven wheel structure, into the wheelshaft spindle. This driving force is transmitted to the wheel carrierlink through the rotatable connection between the wheel shaft spindle,and wheel carrier link. The driving force, acting through carriermanipulation link and axial sliding shaft and frame pivots totals asquat response. These MacPherson Strut systems are incapable ofproducing a stable squat magnitude curve.

A long arm 4-bar semi-parallel link system features a wheel shaftspindle that is rotatably attached to a wheel carrier link. The wheelcarrier link is supported by two semi parallel upper and lower carriermanipulation links, which each pivot around a fixed frame pivot. In thisarrangement, there are a minimum of four pivots connecting the wheelcarrier link to the vehicle frame structure. The wheel carrier link andcarrier manipulation links are arranged so that the frame pivot axisproject towards the right and left sides of the vehicle. In the long arm4-bar semi-parallel link system the axes about which the wheel carrierlink pivots are parallel with the wheel shaft spindle. The long arm4-bar semi parallel system can dynamically perform identically to asingle pivot trailing arm system, but can be useful to overcome somespace constraints of the single pivot trailing arm system. As the drivenwheel is accelerated, the driving force imparted through the wheel tirecombination to the ground through a tire to ground contact patch istransferred through the driven wheel structure, into the wheel shaftspindle. This driving force is transmitted to the wheel carrier linkthrough the rotatable connection between the wheel shaft spindle, andwheel carrier link. The driving force, acting through the wheel carrierlink on the upper and lower carrier manipulation links and frame pivotstotals a squat response. These long arm 4-bar semi-parallel link systemsare incapable of producing a stable squat magnitude curve. To find aninstantaneous squat magnitude, its correlating desired squat forcevector must be graphed. The two wheel carrier link pivots are defined.Carrier manipulation link force lines are drawn so that a force linepasses directly through the center of the two pivot axis of each carriermanipulation link. These two force lines are projected to anintersection point which is called the instant force center. In a longarm 4-bar semi-parallel link system, this instant force center movesdownward as the driven wheel suspension is compressed.

A tuned multi pivot linkage can be used to alter squat characteristicsand obtain a variable squat magnitude curve in a spindle driven wheelsuspension system. A multi link spindle driven suspension systemisolates driving force transmitted to the wheel carrier link through therotatable connection between the wheel shaft spindle and wheel carrierlink. In a 4-bar variation, the driven wheel spindle center defines adriven wheel rotation axis, and is attached to a wheel carrier link,which pivots at one end of a first swinging link. The first carriermanipulation link is pivotally attached to the vehicle chassis at theend opposite of the wheel carrier link pivot. A second carriermanipulation link is also attached to the wheel carrier link. Thissecond carrier manipulation link is attached to the vehicle chassis at adifferent location from the first swinging carrier manipulation link. Asthe driven wheel is accelerated, the driving force imparted through thewheel tire combination to the ground through a tire to ground contactpatch is transferred through the driven wheel structure, into the wheelshaft spindle. This driving force is transmitted to the wheel carrierlink through the rotatable connection between the wheel shaft spindle,and wheel carrier link. The driving force, acting through the wheelcarrier link on the first and second carrier manipulation links andframe pivots totals a squat response. To find instantaneous carriermanipulation link pivot points which will give a desired instantaneoussquat magnitude, its correlating desired squat force vector must begraphed. The two wheel carrier link pivots are defined. Carriermanipulation link force lines are drawn so that a force line passesdirectly through the center of the rearward pivots which are coincidentwith the pivots on the wheel carrier link. The carrier manipulation linkforce lines are drawn so that they intersect on the desired squat forcevector. The first and second vehicle chassis pivots can be positionedupon the corresponding first and second carrier manipulation link forcelines to attain the desired instantaneous squat response. Graphing thecarrier manipulation link force lines and desired squat force vectorstogether overlaid at multiple points in the suspension travel will allowthe designer to choose pivot point locations and kinematical suspensionlayout that can attain a desired variable squat magnitude curve. To findan instantaneous squat magnitude, its correlating desired squat forcevector must be graphed. The two wheel carrier link pivots are defined.Carrier manipulation link force lines are drawn so that a force linepasses directly through the center of the two pivot axis of a firstcarrier manipulation link and second carrier manipulation link. Thesetwo force lines are projected to an intersection point which is calledthe instant force center. In a tuned multi pivot linkage system of theinvention, this instant force center moves upwards in relation togravity or in a direction horizontally closer to the driven wheelrotation axis, or upwards in relation to gravity and in a directionhorizontally closer to the driven wheel rotation axis as the drivenwheel suspension is compressed.

A chain driven powertrain system uses a chain or belt to transmit powerbetween two reasonably parallel shafts. Chain driven systems are verycommon in motorcycle, ATV, and bicycle applications because of theirlight weight, robustness, and simplicity in both manufacturing and use.Simple chain driven systems feature a driving cog and a driven cog, withthe driving cog attached to a power source, and a driven cog rotatablyattached to the rotation axis of a wheel. A driven chain is used totransmit power from the driving cog to the driven cog. When transmittingpower between from the driving cog to the driven cog, the chain forms arelatively straight line between the pitch diameters of the driving anddriven cogs. The driven wheel or wheels is/are attached to a swinginglink or linkage system via a bearing or bushing system, which allowsrotational motion of the driven wheel or wheels in relation to theswinging link or linkage system. More complex chain driven systemsfeature a driving cog and a driven cog, with the driving cog attached toa power source, and a driven cog rotatably attached to the rotation axisof a wheel. A driven chain is used to transmit power from the drivingcog to the driven cog. When transmitting power between from the drivingcog to the driven cog, the chain forms a relatively straight linebetween the pitch diameters of the driving and driven cogs. A drivenidler cog is placed at a position intermediate of the driving cog anddriven cog. This driven idler cog alters the path of the chain and isused for analysis purposes. The driven wheel or wheels is/are attachedto a swinging link or linkage system via a bearing or bushing system,which allows rotational motion of the driven wheel or wheels in relationto the swinging link or linkage system.

Chain driven suspensions typically take one of several forms. Theseinclude single pivot systems, multi link systems, cam/track typesystems, and flexure type systems. The suspensions can also featurevariable chainline type designs, which manipulate a chain force vectorline through the use of a pulley system that moves with the suspension.A single pivot system uses a single pivoting suspension link to transmitforce between a suspended wheel and a chassis. A multi link system usesan arrangement of pivoting suspension links to transmit force between asuspended wheel and a chassis. A cam/track type system that uses slidingelements but does not use links to attain force transfer from a wheelaxle to a chassis is also possible but uncommon in practice. Flexuretype systems use flexing elements to transmit power from a suspendedwheel to a chassis structure. In all types of the chain driven wheelsuspension system mentioned above, the driving force can be representedas a vector drawn perpendicular to the driven wheel axle path. In achain driven suspension, driving force is always the major forcecomponent when compared to chain pull.

There are two internal forces present within a chain driven vehiclechassis that together create a squat response. These two forces aredriving force, and chain pull force.

When a chain driven vehicle is accelerated, force is transferred from apower source to a driving cog. This driving cog transmits its forcethrough a chain to a driven cog. The force direction and magnitudepresent in the tensioned chain are referred to as chain pull force.Fixed chainline type designs are present where at any instantaneouspoint, a single driving cog is fixed rotationally on a chassisstructure, and a driven cog is attached to a suspension member, andforce is transmitted from the driving cog to the driven cog through achain. In this fixed chainline type design, the chainline force vectoris always located at one end by the tensioned chainline tangent pointwhere the chain is fixed in relation to the vehicle chassis structure,and by the tensioned chainline tangent point of the moving pulley at theopposite end.

In variable chainline type designs, which manipulate a chain forcevector line through the use of a pulley system that moves with thesuspension, the chainline force vector can be analyzed at one end by thetensioned chainline tangent point where the chain is fixed in relationto the vehicle chassis structure, and by the tensioned chainline tangentpoint of the moving pulley at the opposite end. Sliding elements canalso be substituted for pulleys in this application.

In variable chainline type designs, which manipulate a chain forcevector line through the use of a pulley system that is fixed to thevehicle chassis, the chainline force vector can be analyzed as locatedat one end by the tensioned chainline tangent point where the chain isfixed in relation to the driven cog at the wheel, and by the tensionedchainline tangent point of the idler pulley fixed at the chassis at theopposite end. Sliding elements can also be substituted for pulleys inthis application.

In the chain driven powertrain, the driven cog is rotatably attached toa wheel/tire combination. The wheel pushes against the ground resultingin friction. As the wheel rotates a driving force transmitted from thecontact patch through the wheel structure and a force is imparted at therear hub axle. This pushing force can be transferred to the chassis viaa wheel suspension system, ultimately pushes the vehicle forward. Thispushing force is referred to as driving force. The driving forcedirection is measured and represented graphically as a driving forcevector drawn from the driven wheel rotation axis, perpendicular to thedriven axle path, where the axle path is defined as a line that asuspended wheel rotational axis travels as a suspension is moved throughsuspension travel. This axle path can be a constant curvature orchanging curvature line depending on suspension layout.

A simple single pivot system features a driven cog that is rotatablyattached to a wheel, which is rotatably attached to a wheel carrier linkwhich pivots around a singular pivot. In this arrangement, the suspendedwheel travels in a constant radius arc. To find the instantaneousswinging link pivot point for a single pivot chain driven system, whichwill give a desired instantaneous squat magnitude, its correlatingdesired squat force vector must be graphed. Because there is only onelink in the single pivot suspension, the swinging link pivot will liecoincident with the driving force line. Desired vehicle geometry isgraphed in a side view. This vehicle geometry will include the size,location, and center points of vehicle tires, powertrain componentlayout, and the direction of gravitational force. A squat layout line isgraphed first. A desired squat force vector is drawn from the center ofa rear wheel contact patch to the desired squat layout point on a squatlayout line as described previously. Next, the chain force vector isgraphed in relation to the powertrain components as describedpreviously. The chain force vector is drawn so that it intersects thesquat force vector. Finally, the driving force vector is drawn from thecenter of the rear wheel axis to the intersection point of the squatforce vector and chain pull force vector. The pivot point for the singlepivot swinging link suspension arm will lie at any point along thedriving force vector to achieve the desired instantaneous squatmagnitude. Graphing the chain pull force vector, and squat force vectorstogether overlaid at multiple points in the suspension travel will allowthe designer to find driving force vectors at multiple points throughthe suspension travel. The crossing point of the overlaid driving forcevectors for different points in the suspension travel define the singlepivot point location and kinematical suspension layout that can attainthe desired squat magnitude curve.

Multi link systems, cam/track (sliding link) type systems, and flexuretype systems feature a driven cog that is rotatably attached to a wheel,which is rotatably attached to a wheel carrier link which moves thewheel along an axle path that is defined by a multi element system. Toaid the analysis of multi-element systems, it is simplest to define ormeasure an axle path which will guide a wheel, and then define theelements that will give the desired axle path later, as opposed totrying to define elements first and measure axle path as a byproductlater to attain a desired result. Multi element systems do not have asingle hardware defined pivot point like a single fixed pivot systemdoes. The multi element systems use combinations of links or cams toproject a virtual or instantaneous pivot point. This pivot point canalways be found at a point along a driving force vector, which is drawnperpendicular to a driven wheel axle path as previously described.

To find an axle path which will give a desired instantaneous squatmagnitude, its correlating desired squat force vectors must be graphed.Desired vehicle geometry is graphed in a side view. This vehiclegeometry will include the size, location, and center points of vehicletires, vehicle ground plane, powertrain component layout, and thedirection of gravitational force. A vehicle wheel suspension systemalways has a minimum suspension travel point, where the suspended wheelis at its zero compressed suspension travel point, and a maximumsuspension travel point, where the suspended wheel is at its 100 percentcompressed suspension travel point. Several overlaid graphs must be madeto obtain a squat magnitude curve. The minimum increment in suspensioncompression displacement that can be used to graph an accurate squatmagnitude curve from the graphical method using squat force vectors aspresented has been found to be 5 percent of total suspension compressiondisplacement between graphed squat force vectors. A squat layout line isgraphed first. A desired squat force vector is drawn from the center ofa driven wheel contact patch to the desired squat layout point on asquat layout line as described previously. Next, the chain force vectoris graphed in relation to the powertrain components as describedpreviously. The chain force vector is drawn so that it intersects thesquat force vector. Finally, the driving force vector is drawn from thecenter of the driven wheel axis to the intersection point of the squatforce vector and chain pull force vector. The instantaneous pivot pointfor the single pivot swinging link suspension arm will lie at any pointalong the driving force vector to achieve the desired instantaneoussquat magnitude. Graphing the chain pull force vector, and squat forcevectors together overlaid at multiple points in the suspension travelwill allow the designer to find driving force vectors at multiple pointsthrough the suspension travel. The crossing point of the overlaiddriving force vectors for different points in the suspension traveldefine the instantaneous pivot point movement through the suspensiontravel, and kinematical suspension layout that can attain the desiredsquat magnitude curve. For multi element systems, there are severalmethods that can define element layout based on a desired axle path, forexample, by using kinematical analysis computer software. Software thatcan perform this specific function is marketed under the names SyMech,which is available from SyMech Inc, 600 Townsend Street, San Francisco,Calif., 94107, USA, and SAM, which is available from ARTAS—EngineeringSoftware, Het Puyven 162, NL-5672 RJ Nuenen, The Netherlands. Thissoftware allows a user to define an axle path, and set parameters suchas mechanical element type, number of mechanical elements, and desiredlocation of anchor components. The software will then suggest multiplelink layout choices that will meet all of the set forth parameters.Graphical analysis can also be performed by hand. In a hand graphicalanalysis, the mechanical components of a multi element system aremeasured at multiple points through the suspension travel. At each pointin the suspension travel, the instant force center of the link system isgraphed. A common 4-bar linkage suspension system features a driven cogthat is rotatably attached to a driven wheel, which is rotatablyattached to a wheel carrier link which is pivotably attached to twoseparate carrier manipulation links. The swinging links are pivotablyattached to a vehicle chassis at their other ends. The instant forcecenter in a 4 bar pivoting linkage system such as shown in FIG. 1 a, isfound by projecting individual link force lines through both pivots ofeach of the two carrier manipulation links that support the wheelcarrier link. The two carrier manipulation link force lines areprojected so that they intersect each other. This intersection point iscommonly known at the instant force center. A driving force line can bedrawn directly from the rotation axis of the driven wheel to thisinstant force center. As the carrier manipulation links rotate on theirpivots, the instant force center position changes in relation to thedriven wheel rotation axis and the vehicle chassis. This causes thedriving force line to move in relation to the chain force line. Becausethe squat force line is defined in part by the location of the drivenwheel contact patch, and the intersection between the driving forcevector and the chain force vector, a change in squat vector directioncan occur. The perpendicular distance from the lower squat definitionline to the point at which this squat direction vector intersects thedrawn squat layout line to is measured and recorded.

Four bar sliding link suspension systems are analyzed identically to 4bar pivoting systems, but the identification of the instant force centeris performed in a slightly different manner due to the constraints ofthe sliding link system. Four bar sliding link systems feature a drivencog that is rotatably attached to a driven wheel, which is rotatablyattached to a wheel carrier link which is pivotably attached to twoseparate sliding carrier manipulation sliding blocks. The individualcarrier manipulation sliding blocks move on individual sliding rails.The instant force center in a 4 bar sliding linkage system is found byprojecting individual sliding link force lines centered at the pivots ofeach of the two carrier manipulation sliding block that support thewheel carrier link. The carrier manipulation sliding block force linesare projected perpendicular to the sliding rail so that the two carriermanipulation sliding black force lines intersect each other. Thisintersection can be referred to as the instant force center. A drivingforce line can be drawn directly from the rotation axis of the drivenwheel to this instant force center. As the carrier manipulation slidingblocks slide on their respective sliding rails, the instant force centerposition changes in relation to the driven wheel rotation axis and thevehicle chassis. This causes the driving force line to move in relationto the chain force line. Because the squat force line is defined in partby the location of the driven wheel contact patch, and the intersectionbetween the driving force vector and the chain force vector, a change insquat vector direction can occur. The perpendicular distance from thelower squat definition line to the point at which this squat directionvector intersects the drawn squat layout line to is measured andrecorded.

Measurement of multi element systems to determine axle path can be donegraphically, or by using measurement equipment. Using measurementequipment, the vehicle can be rigidly mounted and oriented so that thesuspended wheel can be moved freely through measured points in itssuspension travel while the chassis stays stationary. In a side vieworientation, the horizontal and vertical distance from the suspendedwheel rotation axis to a fixed point on the vehicle frame at multiplepoints in the suspension travel is taken. As the suspension is cycledthrough suspension travel, the corresponding measurements of horizontaland vertical distance form a wheel rotation axis travel path in relationto the vehicle chassis. This path is referred to as the axle path.

Common graphical kinematical method requires that the display of adriving cog 27 as its driving cog pitch diameter 47 for the accuratecalculation of force lines.

Analysis has shown that most vehicles accelerate during a finitepercentage of their driven wheel travel distance. For the majority ofvehicles analyzed, the majority of acceleration occurs within a range of25 percent of the total driven wheel travel distance. Analysis has shownthat a vehicle with a compressible suspension system using a chaindriven suspended wheel achieves the squat magnitude curve 17 of thecurrent invention and as shown in FIG. 9 and FIG. 10, by having a layoutthat features a driven cog that is rotatably attached to a driven wheel,which is rotatably attached to a wheel carrier link which is pivotablyattached to separate upper and second carrier manipulation links. Theupper and second carrier manipulation links are pivotably attached to avehicle chassis at their other ends. The upper and second carriermanipulation links rotate in the same rotational direction about theirrespective fixed axis at the vehicle chassis as shown in FIGS. 1 a, 1 b,1 c, and 1 d. The first carrier manipulation link is arranged inrelation to the second carrier manipulation link so that the instantforce center 24 projected by the two carrier manipulation links, followsan instant force center path 45 as the suspension is moved through itsdriven wheel suspension travel distance 15. The location of this instantforce center path 45 in relation to the driving cog pitch diameter 47 isimportant in creating a stable squat magnitude curve 17. The instantforce center path 45 has a defined instant force center path focus 46which is the geometrically graphed as the intersection point of twolines which lie coincident to two points on the same path, andperpendicular to said path. Greater graphing accuracy of the instantforce center path focus 46 location can be achieved when the two saidpoints on the said path are closer together. Because the majority ofacceleration for the majority of vehicles analyzed happens within 25percent of the driven wheel suspension travel distance, the instantforce center path focus 46 of the invention will lie within the drivingcog pitch diameter 47 during at least 25 percent of the driven wheelsuspension travel distance.

Analysis has shown that a vehicle with a compressible suspension systemusing a chain driven suspended wheel achieves the squat magnitude curve17 of the current invention and as shown in FIG. 11 and FIG. 12, byhaving a layout that features a driven cog that is rotatably attached toa driven wheel, which is rotatably attached to a wheel carrier linkwhich is pivotably attached to separate upper and second carriermanipulation links. The upper and second carrier manipulation links arepivotably attached to a vehicle chassis at their other ends. The upperand second carrier manipulation links rotate in opposite directionsabout their respective fixed axis at the vehicle chassis as shown inFIGS. 4 a and 4 b. The first carrier manipulation link is arranged inrelation to the second carrier manipulation link so that the instantforce center 24 projected by the two carrier manipulation links, followsan instant force center path 45 as the suspension is moved through itsdriven wheel suspension travel distance 15. The location of this instantforce center path 45 in relation to the driving cog pitch diameter 47 isimportant in creating a stable squat magnitude curve 17. The instantforce center path 45 has a defined instant force center path focus 46which is the geometrically graphed as the intersection point of twolines which lie coincident to two points on the same path, andperpendicular to said path. Greater graphing accuracy of the instantforce center path focus 46 location can be achieved when the two saidpoints on the said path are closer together. Because the majority ofacceleration for the majority of vehicles analyzed happens within 25percent of the driven wheel suspension travel distance, the instantforce center path focus 46 of the invention will lie within a drivingcog pitch diameter 47 during at least 25 percent of the driven wheelsuspension travel distance.

Kinematical analysis shows that a shaft driven wheel suspension of theinvention can be attained by arranging suspension components in a methodthat will project an instant force center 24 that moves in an upwarddirection, or in a direction horizontally closer to the driven wheelrotation axis, or in an upward in relation to gravity and in a directionhorizontally closer to the driven wheel rotation axis as the drivenwheel moves compressively through its driven wheel suspension traveldistance. Movement of an instant force center 24 in an upward directionin relation to gravity or in a direction horizontally closer to thedriven wheel rotation axis, or in an upward in relation to gravity andin a direction horizontally closer to the driven wheel rotation axis asthe driven wheel moves compressively through its driven wheel suspensiontravel distance can attain a stable squat magnitude of the inventionbecause a driven wheel moves compressively through its driven wheelsuspension travel distance in an or partially in an upward directionagainst gravity.

Kinematical analysis shows that a spindle driven wheel suspension of theinvention can be attained by arranging suspension components in a methodthat will project an instant force center 24 that moves in an upwarddirection, or in a direction horizontally closer to the driven wheelrotation axis, or in an upward in relation to gravity and in a directionhorizontally closer to the driven wheel rotation axis as the drivenwheel moves compressively through its driven wheel suspension traveldistance. Movement of an instant force center 24 in an upward directionin relation to gravity or in a direction horizontally closer to thedriven wheel rotation axis, or in an upward in relation to gravity andin a direction horizontally closer to the driven wheel rotation axis asthe driven wheel moves compressively through its driven wheel suspensiontravel distance can attain a stable squat magnitude of the inventionbecause a driven wheel moves compressively through its driven wheelsuspension travel distance in an or partially in an upward directionagainst gravity.

Analysis has shown that a vehicle with a compressible suspension systemusing a shaft driven suspended wheel achieves the squat magnitude curve17 of the current invention and as shown in FIGS. 5, 6, 7, and 8, byhaving a layout that features a driven cog that is rotatably attached toa driven wheel, which is rotatably attached to a wheel carrier linkwhich is pivotably attached to separate upper and second carriermanipulation links. The upper and second carrier manipulation links arepivotably attached to a vehicle chassis at their other ends. The upperand second carrier manipulation links rotate in a contra rotationaldirection about their fixed axes at the vehicle chassis as shown inFIGS. 2 a, 2 b, 2 c, and 2 d. The first carrier manipulation link isarranged in relation to the second carrier manipulation link so that theinstant force center 24 projected by the two carrier manipulation links,moves in an upward direction in relation to gravity, or in a directionhorizontally closer to the driven wheel rotation axis, or upward inrelation to gravity and in a direction horizontally closer to the drivenwheel rotation axis as the driven wheel moves compressively through itsdriven wheel suspension travel distance. This upward, or rearward, orupward and rearward movement of the instant force center 24 as thesuspension rear wheel rotation axis moves compressively through itsdriven wheel suspension travel distance 15 along its axle path 14achieves the squat magnitude curve 17 of the current invention.

Analysis has shown that a vehicle with a compressible suspension systemusing a shaft driven suspended wheel achieves the squat magnitude curve17 of the current invention and as shown in FIGS. 5, 6, 7, and 8, byhaving a layout that features a driven cog that is rotatably attached toa driven wheel, which is rotatably attached to a wheel carrier linkwhich is pivotably attached to separate upper and second carriermanipulation links. The upper and second carrier manipulation links arepivotably attached to a vehicle chassis at their other ends. The upperand second carrier manipulation links rotate in the same rotationaldirection about their fixed axes at the vehicle chassis as shown inFIGS. 5 a and 5 b. The first carrier manipulation link is arranged inrelation to the second carrier manipulation link so that the instantforce center 24 projected by the two carrier manipulation links, movesin an upward direction in relation to gravity, or in a directionhorizontally closer to the driven wheel rotation axis, or upward inrelation to gravity and in a direction horizontally closer to the drivenwheel rotation axis as the driven wheel moves compressively through itsdriven wheel suspension travel distance. This upward, or rearward, orupward and rearward movement of the instant force center 24 as thesuspension rear wheel rotation axis moves compressively through itsdriven wheel suspension travel distance 15 along its axle path 14achieves the squat magnitude curve 17 of the current invention.

Analysis has shown that a vehicle with a compressible suspension systemusing a spindle driven suspended wheel achieves the squat magnitudecurve 17 of the current invention and as shown in FIGS. 5, 6, 7, and 8,by having a layout that features a driven cog that is rotatably attachedto a driven wheel, which is rotatably attached to a wheel carrier linkwhich is pivotably attached to separate upper and second carriermanipulation links. The upper and second carrier manipulation links arepivotably attached to a vehicle chassis at their other ends. The upperand second carrier manipulation links rotate in a contra rotationaldirection about their fixed axes at the vehicle chassis as shown inFIGS. 2 a, 2 b, 2 c, and 2 d. The first carrier manipulation link isarranged in relation to the second carrier manipulation link so that theinstant force center 24 projected by the two carrier manipulation links,moves in an upward direction in relation to gravity, or in a directionhorizontally closer to the driven wheel rotation axis, or upward inrelation to gravity and in a direction horizontally closer to the drivenwheel rotation axis as the driven wheel moves compressively through itsdriven wheel suspension travel distance. This upward, or rearward, orupward and rearward movement of the instant force center 24 as thesuspension rear wheel rotation axis moves compressively through itsdriven wheel suspension travel distance 15 along its axle path 14achieves the squat magnitude curve 17 of the current invention.

Analysis has shown that a vehicle with a compressible suspension systemusing a spindle driven suspended wheel achieves the squat magnitudecurve 17 of the current invention and as shown in FIGS. 5, 6, 7, and 8,by having a layout that features a driven cog that is rotatably attachedto a driven wheel, which is rotatably attached to a wheel carrier linkwhich is pivotably attached to separate upper and second carriermanipulation links. The upper and second carrier manipulation links arepivotably attached to a vehicle chassis at their other ends. The upperand second carrier manipulation links rotate in the same rotationaldirection about their fixed axes at the vehicle chassis as shown inFIGS. 5 a and 5 b. The first carrier manipulation link is arranged inrelation to the second carrier manipulation link so that the instantforce center 24 projected by the two carrier manipulation links, movesin an upward direction in relation to gravity, or in a directionhorizontally closer to the driven wheel rotation axis, or upward inrelation to gravity and in a direction horizontally closer to the drivenwheel rotation axis as the driven wheel moves compressively through itsdriven wheel suspension travel distance. This upward, or rearward, orupward and rearward movement of the instant force center 24 as thesuspension rear wheel rotation axis moves compressively through itsdriven wheel suspension travel distance 15 along its axle path 14achieves the squat magnitude curve 17 of the current invention.

Analysis has shown that a squat magnitude curve 17 as shown in FIGS.5,6,7, and 8 can be produced by the shaft driven vehicle suspensionlayouts shown in FIGS. 2 a, 2 b, 2 c, 2 d, 3 a, 3 b, 3 c, 3 d, 5 a, 5 b6 a, and 6 b.

Analysis has shown that a squat magnitude curve 17 as shown in FIGS. 9and 10 can be produced by the chain driven vehicle suspension layoutshown in FIGS. 1 a, 1 b, 1 c, and 1 d.

Analysis has shown that a squat magnitude curve 17 as shown in FIGS. 11and 12 can be produced by the chain driven vehicle suspension layoutshown in FIGS. 4 a and 4 b.

Analysis has shown that a squat magnitude curve 17 as shown in FIGS. 11and 12 can be produced by the chain driven vehicle suspension layoutshown in FIG. 38.

The present invention is not to be limited in scope by the specificembodiments described herein, which are intended as single illustrationsof individual aspects of the invention, and functionally equivalentmethods and components are within the scope of the invention. Indeed,various modifications of the invention, in addition to those shown anddescribed herein, will become apparent to those skilled in the art fromthe foregoing description. Such modifications are intended to fallwithin the scope of the appended claims. All cited publications,patents, and patent applications are herein incorporated by reference intheir entirety.

1. A vehicle suspension system for a shaft driven wheel suspension,wherein said suspension system projects an instant force center whichmoves in an upward direction in relation to gravity as the vehiclesuspension is compressed while standing on level ground.
 2. A vehiclesuspension system for a shaft driven wheel suspension, wherein saidsuspension system projects an instant force center which moves in adirection horizontally closer to the driven wheel rotation axis as thevehicle suspension is compressed while standing on level ground. 3-6.(canceled)
 7. A suspension system for a chain driven rear wheelsuspension, with a driving cog, where said driving cog has a pitchdiameter, wherein said suspension system projects an instant forcecenter which moves in an upwards direction as the vehicle suspension iscompressed and said instant force center follows an instant force centerpath, and said instant force center path describes an instant forcecenter focus, and said instant force center focus lies within the areadescribed by the driving cog pitch diameter at a point or points duringthe suspension compression.